Revert of add ImageShader, sharing code with its Bitmap cousin (patchset #10 id:180001 of https://codereview.chromium.org/1342113002/ )

Reason for revert:
Failing ImageNewShaderTest on both Android (Tegra3 GPU) and iOS bots.

e.g.

/Users/chrome-bot/buildbot/skiabot-ipad4-000/build/slave/workdir/build/skia/tests/
	ImageNewShaderTest.cpp:24	0 == memcmp(bm1.getPixels(), bm2.getPixels(), bm1.getSize())
	ImageNewShaderTest.cpp:95	0xFFFF0000 == bmt.getColor(0, y)
	ImageNewShaderTest.cpp:98	0xFFDEDEDE == bmt.getColor(x, y)
	ImageNewShaderTest.cpp:98	0xFFDEDEDE == bmt.getColor(x, y)
	ImageNewShaderTest.cpp:98	0xFFDEDEDE == bmt.getColor(x, y)
	ImageNewShaderTest.cpp:98	0xFFDEDEDE == bmt.getColor(x, y)
	ImageNewShaderTest.cpp:95	0xFFFF0000 == bmt.getColor(0, y)
...

Original issue's description:
> add ImageShader, sharing code with its Bitmap cousin
>
> This is done by having abstracted the BitmapShaderContext to take a BitmapProvider, instead of just a bitmap. This allows us to share all of that code between SkBitmap and SkImage, since both are valid providers.
>
> It also means that we can simplify SkImage_Base to not need a virtual for onNewShader, since ALL images can uniformly be turned into a shader now.
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/0b93e3149d2cb30860c51f9f3204ae811d9a97ca

TBR=fmalita@chromium.org,bsalomon@google.com,robertphillips@google.com,reed@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1355863002

8 files changed, 40 insertions, 191 deletions

diff --git a/src/image/SkImage.cpp b/src/image/SkImage.cpp
index 975d7ba803..6f4655758e 100644
--- a/src/image/SkImage.cpp
+++ b/src/image/SkImage.cpp
@@ -11,7 +11,6 @@
 #include "SkData.h"
 #include "SkImageGenerator.h"
 #include "SkImagePriv.h"
-#include "SkImageShader.h"
 #include "SkImage_Base.h"
 #include "SkNextID.h"
 #include "SkPixelRef.h"
@@ -70,7 +69,7 @@ void SkImage::preroll(GrContext* ctx) const {
 SkShader* SkImage::newShader(SkShader::TileMode tileX,
                              SkShader::TileMode tileY,
                              const SkMatrix* localMatrix) const {
-    return SkImageShader::Create(this, tileX, tileY, localMatrix);
+    return as_IB(this)->onNewShader(tileX, tileY, localMatrix);
 }
 
 SkData* SkImage::encode(SkImageEncoder::Type type, int quality) const {
diff --git a/src/image/SkImageShader.cpp b/src/image/SkImageShader.cpp
deleted file mode 100644
index 58eddf3f7d..0000000000
--- a/src/image/SkImageShader.cpp
+++ /dev/null
@@ -1,145 +0,0 @@
-/*
- * Copyright 2015 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "SkBitmapProcShader.h"
-#include "SkBitmapProvider.h"
-#include "SkImage_Base.h"
-#include "SkImageShader.h"
-#include "SkReadBuffer.h"
-#include "SkWriteBuffer.h"
-
-SkImageShader::SkImageShader(const SkImage* img, TileMode tmx, TileMode tmy, const SkMatrix* matrix)
-    : INHERITED(matrix)
-    , fImage(SkRef(img))
-    , fTileModeX(tmx)
-    , fTileModeY(tmy)
-{}
-
-SkFlattenable* SkImageShader::CreateProc(SkReadBuffer& buffer) {
-    const TileMode tx = (TileMode)buffer.readUInt();
-    const TileMode ty = (TileMode)buffer.readUInt();
-    SkMatrix matrix;
-    buffer.readMatrix(&matrix);
-    SkAutoTUnref<SkImage> img(buffer.readImage());
-    if (!img) {
-        return nullptr;
-    }
-    return new SkImageShader(img, tx, ty, &matrix);
-}
-
-void SkImageShader::flatten(SkWriteBuffer& buffer) const {
-    buffer.writeUInt(fTileModeX);
-    buffer.writeUInt(fTileModeY);
-    buffer.writeMatrix(this->getLocalMatrix());
-    buffer.writeImage(fImage);
-}
-
-bool SkImageShader::isOpaque() const {
-    return fImage->isOpaque();
-}
-
-size_t SkImageShader::contextSize() const {
-    return SkBitmapProcShader::ContextSize();
-}
-
-SkShader::Context* SkImageShader::onCreateContext(const ContextRec& rec, void* storage) const {
-    return SkBitmapProcShader::MakeContext(*this, fTileModeX, fTileModeY,
-                                           SkBitmapProvider(fImage), rec, storage);
-}
-
-SkShader* SkImageShader::Create(const SkImage* image, TileMode tx, TileMode ty,
-                                const SkMatrix* localMatrix) {
-    if (!image) {
-        return nullptr;
-    }
-    return new SkImageShader(image, tx, ty, localMatrix);
-}
-
-#ifndef SK_IGNORE_TO_STRING
-void SkImageShader::toString(SkString* str) const {
-    const char* gTileModeName[SkShader::kTileModeCount] = {
-        "clamp", "repeat", "mirror"
-    };
-
-    str->appendf("ImageShader: ((%s %s) ", gTileModeName[fTileModeX], gTileModeName[fTileModeY]);
-    fImage->toString(str);
-    this->INHERITED::toString(str);
-    str->append(")");
-}
-#endif
-
-///////////////////////////////////////////////////////////////////////////////////////////////////
-
-#if SK_SUPPORT_GPU
-
-#include "GrTextureAccess.h"
-#include "SkGr.h"
-#include "effects/GrSimpleTextureEffect.h"
-#include "effects/GrBicubicEffect.h"
-#include "effects/GrExtractAlphaFragmentProcessor.h"
-#include "effects/GrSimpleTextureEffect.h"
-
-const GrFragmentProcessor* SkImageShader::asFragmentProcessor(GrContext* context,
-                                                              const SkMatrix& viewM,
-                                                              const SkMatrix* localMatrix,
-                                                              SkFilterQuality filterQuality,
-                                                              GrProcessorDataManager* mgr) const {
-    SkMatrix matrix;
-    matrix.setIDiv(fImage->width(), fImage->height());
-
-    SkMatrix lmInverse;
-    if (!this->getLocalMatrix().invert(&lmInverse)) {
-        return nullptr;
-    }
-    if (localMatrix) {
-        SkMatrix inv;
-        if (!localMatrix->invert(&inv)) {
-            return nullptr;
-        }
-        lmInverse.postConcat(inv);
-    }
-    matrix.preConcat(lmInverse);
-
-    SkShader::TileMode tm[] = { fTileModeX, fTileModeY };
-
-    // Must set wrap and filter on the sampler before requesting a texture. In two places below
-    // we check the matrix scale factors to determine how to interpret the filter quality setting.
-    // This completely ignores the complexity of the drawVertices case where explicit local coords
-    // are provided by the caller.
-    bool doBicubic;
-    GrTextureParams::FilterMode textureFilterMode =
-    GrSkFilterQualityToGrFilterMode(filterQuality, viewM, this->getLocalMatrix(), &doBicubic);
-    GrTextureParams params(tm, textureFilterMode);
-
-    SkImageUsageType usageType;
-    if (kClamp_TileMode == fTileModeX && kClamp_TileMode == fTileModeY) {
-        usageType = kUntiled_SkImageUsageType;
-    } else if (GrTextureParams::kNone_FilterMode == textureFilterMode) {
-        usageType = kTiled_Unfiltered_SkImageUsageType;
-    } else {
-        usageType = kTiled_Filtered_SkImageUsageType;
-    }
-
-    SkAutoTUnref<GrTexture> texture(as_IB(fImage)->asTextureRef(context, usageType));
-    if (!texture) {
-        return nullptr;
-    }
-
-    SkAutoTUnref<GrFragmentProcessor> inner;
-    if (doBicubic) {
-        inner.reset(GrBicubicEffect::Create(mgr, texture, matrix, tm));
-    } else {
-        inner.reset(GrSimpleTextureEffect::Create(mgr, texture, matrix, params));
-    }
-
-    if (GrPixelConfigIsAlphaOnly(texture->config())) {
-        return SkRef(inner.get());
-    }
-    return GrExtractAlphaFragmentProcessor::Create(inner);
-}
-
-#endif
diff --git a/src/image/SkImageShader.h b/src/image/SkImageShader.h
deleted file mode 100644
index fdd7976aad..0000000000
--- a/src/image/SkImageShader.h
+++ /dev/null
@@ -1,44 +0,0 @@
-/*
- * Copyright 2015 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef SkImageShader_DEFINED
-#define SkImageShader_DEFINED
-
-#include "SkImage.h"
-#include "SkShader.h"
-
-class SkImageShader : public SkShader {
-public:
-    static SkShader* Create(const SkImage*, TileMode tx, TileMode ty, const SkMatrix* localMatrix);
-
-    bool isOpaque() const override;
-    size_t contextSize() const override;
-
-    SK_TO_STRING_OVERRIDE()
-    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkImageShader)
-
-#if SK_SUPPORT_GPU
-    const GrFragmentProcessor* asFragmentProcessor(GrContext*, const SkMatrix& viewM,
-                                                   const SkMatrix*, SkFilterQuality,
-                                                   GrProcessorDataManager*) const override;
-#endif
-
-protected:
-    void flatten(SkWriteBuffer&) const override;
-    Context* onCreateContext(const ContextRec&, void* storage) const override;
-
-    SkAutoTUnref<const SkImage> fImage;
-    const TileMode              fTileModeX;
-    const TileMode              fTileModeY;
-
-private:
-    SkImageShader(const SkImage*, TileMode tx, TileMode ty, const SkMatrix* localMatrix);
-
-    typedef SkShader INHERITED;
-};
-
-#endif
diff --git a/src/image/SkImage_Base.h b/src/image/SkImage_Base.h
index bbe70a7e4a..d0cb8d5840 100644
--- a/src/image/SkImage_Base.h
+++ b/src/image/SkImage_Base.h
@@ -56,6 +56,10 @@ public:
     // Caller must call unref when they are done.
     virtual GrTexture* asTextureRef(GrContext*, SkImageUsageType) const = 0;
 
+    virtual SkShader* onNewShader(SkShader::TileMode,
+                                  SkShader::TileMode,
+                                  const SkMatrix* localMatrix) const { return nullptr; }
+
     // newWidth > 0, newHeight > 0, subset either nullptr or a proper subset of this bounds
     virtual SkImage* onNewImage(int newWidth, int newHeight, const SkIRect* subset,
                                 SkFilterQuality) const;
diff --git a/src/image/SkImage_Generator.cpp b/src/image/SkImage_Generator.cpp
index f0bf7e3641..0f1fa3692c 100644
--- a/src/image/SkImage_Generator.cpp
+++ b/src/image/SkImage_Generator.cpp
@@ -28,6 +28,11 @@ public:
 
     bool getROPixels(SkBitmap*) const override;
     GrTexture* asTextureRef(GrContext*, SkImageUsageType) const override;
+
+    SkShader* onNewShader(SkShader::TileMode,
+                          SkShader::TileMode,
+                          const SkMatrix* localMatrix) const override;
+
     bool onIsLazyGenerated() const override { return true; }
 
 private:
@@ -38,6 +43,17 @@ private:
 
 ///////////////////////////////////////////////////////////////////////////////
 
+SkShader* SkImage_Generator::onNewShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
+                                         const SkMatrix* localMatrix) const {
+    // TODO: need a native Shader that takes Cacherator (or this image) so we can natively return
+    // textures as output from the shader.
+    SkBitmap bm;
+    if (this->getROPixels(&bm)) {
+        return SkShader::CreateBitmapShader(bm, tileX, tileY, localMatrix);
+    }
+    return nullptr;
+}
+
 SkSurface* SkImage_Generator::onNewSurface(const SkImageInfo& info,
                                            const SkSurfaceProps& props) const {
     return SkSurface::NewRaster(info, &props);
diff --git a/src/image/SkImage_Gpu.cpp b/src/image/SkImage_Gpu.cpp
index 527bcc3ef5..163e62e02d 100644
--- a/src/image/SkImage_Gpu.cpp
+++ b/src/image/SkImage_Gpu.cpp
@@ -49,6 +49,13 @@ extern void SkTextureImageApplyBudgetedDecision(SkImage* image) {
     }
 }
 
+SkShader* SkImage_Gpu::onNewShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
+                                   const SkMatrix* localMatrix) const {
+    SkBitmap bm;
+    GrWrapTextureInBitmap(fTexture, this->width(), this->height(), this->isOpaque(), &bm);
+    return SkShader::CreateBitmapShader(bm, tileX, tileY, localMatrix);
+}
+
 bool SkImage_Gpu::getROPixels(SkBitmap* dst) const {
     if (SkBitmapCache::Find(this->uniqueID(), dst)) {
         SkASSERT(dst->getGenerationID() == this->uniqueID());
diff --git a/src/image/SkImage_Gpu.h b/src/image/SkImage_Gpu.h
index cc576c499c..d168fb6853 100644
--- a/src/image/SkImage_Gpu.h
+++ b/src/image/SkImage_Gpu.h
@@ -40,6 +40,9 @@ public:
     GrTexture* asTextureRef(GrContext* ctx, SkImageUsageType usage) const override;
 
     GrTexture* peekTexture() const override { return fTexture; }
+    SkShader* onNewShader(SkShader::TileMode,
+                          SkShader::TileMode,
+                          const SkMatrix* localMatrix) const override;
     bool isOpaque() const override;
     SkSurface* onNewSurface(const SkImageInfo&, const SkSurfaceProps&) const override;
     bool onReadPixels(const SkImageInfo&, void* dstPixels, size_t dstRowBytes,
diff --git a/src/image/SkImage_Raster.cpp b/src/image/SkImage_Raster.cpp
index 18d6ba6fd7..67498f0e11 100644
--- a/src/image/SkImage_Raster.cpp
+++ b/src/image/SkImage_Raster.cpp
@@ -80,6 +80,10 @@ public:
 
     SkPixelRef* getPixelRef() const { return fBitmap.pixelRef(); }
 
+    SkShader* onNewShader(SkShader::TileMode,
+                          SkShader::TileMode,
+                          const SkMatrix* localMatrix) const override;
+
     bool isOpaque() const override;
     bool onAsLegacyBitmap(SkBitmap*, LegacyBitmapMode) const override;
 
@@ -140,6 +144,11 @@ SkImage_Raster::SkImage_Raster(const Info& info, SkPixelRef* pr, const SkIPoint&
 
 SkImage_Raster::~SkImage_Raster() {}
 
+SkShader* SkImage_Raster::onNewShader(SkShader::TileMode tileX, SkShader::TileMode tileY,
+                                      const SkMatrix* localMatrix) const {
+    return SkShader::CreateBitmapShader(fBitmap, tileX, tileY, localMatrix);
+}
+
 SkSurface* SkImage_Raster::onNewSurface(const SkImageInfo& info, const SkSurfaceProps& props) const {
     return SkSurface::NewRaster(info, &props);
 }