Revert of Add color xform support to SkWebpCodec (patchset #2 id:80001 of https://codereview.chromium.org/2294993002/ )

Reason for revert:
Windows bots hate it when I upload new images.

Original issue's description:
> Add color xform support to SkWebpCodec
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2294993002
>
> Committed: https://skia.googlesource.com/skia/+/828ed1777da74692d0c8a5834017929f5aedcc6b

TBR=scroggo@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review-Url: https://codereview.chromium.org/2318253004

3 files changed, 25 insertions, 69 deletions

diff --git a/src/codec/SkCodecPriv.h b/src/codec/SkCodecPriv.h
index 9a8a43e835..17494074b3 100644
--- a/src/codec/SkCodecPriv.h
+++ b/src/codec/SkCodecPriv.h
@@ -331,8 +331,4 @@ static inline bool needs_color_xform(const SkImageInfo& dstInfo, const SkImageIn
     return !isLegacy && (needsPremul || isF16 || srcDstNotEqual);
 }
 
-static inline SkAlphaType select_alpha_xform(SkAlphaType dstAlphaType, SkAlphaType srcAlphaType) {
-    return (kOpaque_SkAlphaType == srcAlphaType) ? kOpaque_SkAlphaType : dstAlphaType;
-}
-
 #endif // SkCodecPriv_DEFINED
diff --git a/src/codec/SkPngCodec.cpp b/src/codec/SkPngCodec.cpp
index ac7238d3e9..1b8cadbf5e 100644
--- a/src/codec/SkPngCodec.cpp
+++ b/src/codec/SkPngCodec.cpp
@@ -94,6 +94,10 @@ private:
 };
 #define AutoCleanPng(...) SK_REQUIRE_LOCAL_VAR(AutoCleanPng)
 
+static inline SkAlphaType xform_alpha_type(SkAlphaType dstAlphaType, SkAlphaType srcAlphaType) {
+    return (kOpaque_SkAlphaType == srcAlphaType) ? kOpaque_SkAlphaType : dstAlphaType;
+}
+
 // Note: SkColorTable claims to store SkPMColors, which is not necessarily the case here.
 bool SkPngCodec::createColorTable(const SkImageInfo& dstInfo, int* ctableCount) {
 
@@ -151,8 +155,8 @@ bool SkPngCodec::createColorTable(const SkImageInfo& dstInfo, int* ctableCount)
     if (fColorXform && kRGBA_F16_SkColorType != dstInfo.colorType()) {
         SkColorType xformColorType = is_rgba(dstInfo.colorType()) ?
                 kRGBA_8888_SkColorType : kBGRA_8888_SkColorType;
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
-                                                        this->getInfo().alphaType());
+        SkAlphaType xformAlphaType = xform_alpha_type(dstInfo.alphaType(),
+                                                      this->getInfo().alphaType());
         fColorXform->apply(colorTable, colorTable, numColors, xformColorType, xformAlphaType);
     }
 
@@ -443,8 +447,8 @@ public:
             return y;
         }
 
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
-                                                        this->getInfo().alphaType());
+        SkAlphaType xformAlphaType = xform_alpha_type(dstInfo.alphaType(),
+                                                      this->getInfo().alphaType());
         int width = fSwizzler ? fSwizzler->swizzleWidth() : dstInfo.width();
 
         for (; y < count; y++) {
@@ -529,8 +533,8 @@ public:
             }
         }
 
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
-                                                        this->getInfo().alphaType());
+        SkAlphaType xformAlphaType = xform_alpha_type(dstInfo.alphaType(),
+                                                      this->getInfo().alphaType());
         int width = fSwizzler ? fSwizzler->swizzleWidth() : dstInfo.width();
         srcRow = storage.get();
         for (int y = 0; y < count; y++) {
diff --git a/src/codec/SkWebpCodec.cpp b/src/codec/SkWebpCodec.cpp
index 0c3aa402bd..c12b1df5ed 100644
--- a/src/codec/SkWebpCodec.cpp
+++ b/src/codec/SkWebpCodec.cpp
@@ -6,7 +6,6 @@
  */
 
 #include "SkCodecPriv.h"
-#include "SkColorSpaceXform.h"
 #include "SkWebpCodec.h"
 #include "SkStreamPriv.h"
 #include "SkTemplates.h"
@@ -144,20 +143,20 @@ SkCodec* SkWebpCodec::NewFromStream(SkStream* stream) {
                            streamDeleter.release(), demux.release(), std::move(data));
 }
 
-static bool webp_conversion_possible(const SkImageInfo& dst, const SkImageInfo& src,
-                                     SkColorSpaceXform* colorXform) {
+// This version is slightly different from SkCodecPriv's version of conversion_possible. It
+// supports both byte orders for 8888.
+static bool webp_conversion_possible(const SkImageInfo& dst, const SkImageInfo& src) {
     if (!valid_alpha(dst.alphaType(), src.alphaType())) {
         return false;
     }
 
     switch (dst.colorType()) {
-        case kRGBA_F16_SkColorType:
-            return nullptr != colorXform;
+        // Both byte orders are supported.
         case kBGRA_8888_SkColorType:
         case kRGBA_8888_SkColorType:
             return true;
         case kRGB_565_SkColorType:
-            return nullptr == colorXform && src.alphaType() == kOpaque_SkAlphaType;
+            return src.alphaType() == kOpaque_SkAlphaType;
         default:
             return false;
     }
@@ -211,15 +210,8 @@ bool SkWebpCodec::onGetValidSubset(SkIRect* desiredSubset) const {
 
 SkCodec::Result SkWebpCodec::onGetPixels(const SkImageInfo& dstInfo, void* dst, size_t rowBytes,
                                          const Options& options, SkPMColor*, int*,
-                                         int* rowsDecodedPtr) {
-
-    std::unique_ptr<SkColorSpaceXform> colorXform = nullptr;
-    if (needs_color_xform(dstInfo, this->getInfo())) {
-        colorXform = SkColorSpaceXform::New(sk_ref_sp(this->getInfo().colorSpace()),
-                                            sk_ref_sp(dstInfo.colorSpace()));
-    }
-
-    if (!webp_conversion_possible(dstInfo, this->getInfo(), colorXform.get())) {
+                                         int* rowsDecoded) {
+    if (!webp_conversion_possible(dstInfo, this->getInfo())) {
         return kInvalidConversion;
     }
 
@@ -277,28 +269,13 @@ SkCodec::Result SkWebpCodec::onGetPixels(const SkImageInfo& dstInfo, void* dst,
         config.options.scaled_height = dstDimensions.height();
     }
 
-    // FIXME (msarett):
-    // Lossless webp is encoded as BGRA.  In that case, it would be more efficient to
-    // to decode BGRA and apply the color xform to a BGRA buffer.
-    config.output.colorspace = colorXform ? MODE_RGBA :
-            webp_decode_mode(dstInfo.colorType(), dstInfo.alphaType() == kPremul_SkAlphaType);
+    config.output.colorspace = webp_decode_mode(dstInfo.colorType(),
+            dstInfo.alphaType() == kPremul_SkAlphaType);
+    config.output.u.RGBA.rgba = (uint8_t*) dst;
+    config.output.u.RGBA.stride = (int) rowBytes;
+    config.output.u.RGBA.size = dstInfo.getSafeSize(rowBytes);
     config.output.is_external_memory = 1;
 
-    // We will decode the entire image and then perform the color transform.  libwebp
-    // does not provide a row-by-row API.  This is a shame particularly in the F16 case,
-    // where we need to allocate an extra image-sized buffer.
-    SkAutoTMalloc<uint32_t> pixels;
-    if (kRGBA_F16_SkColorType == dstInfo.colorType()) {
-        pixels.reset(dstDimensions.width() * dstDimensions.height());
-        config.output.u.RGBA.rgba = (uint8_t*) pixels.get();
-        config.output.u.RGBA.stride = (int) dstDimensions.width() * sizeof(uint32_t);
-        config.output.u.RGBA.size = config.output.u.RGBA.stride * dstDimensions.height();
-    } else {
-        config.output.u.RGBA.rgba = (uint8_t*) dst;
-        config.output.u.RGBA.stride = (int) rowBytes;
-        config.output.u.RGBA.size = dstInfo.getSafeSize(rowBytes);
-    }
-
     WebPIterator frame;
     SkAutoTCallVProc<WebPIterator, WebPDemuxReleaseIterator> autoFrame(&frame);
     // If this succeeded in NewFromStream(), it should succeed again here.
@@ -309,36 +286,15 @@ SkCodec::Result SkWebpCodec::onGetPixels(const SkImageInfo& dstInfo, void* dst,
         return kInvalidInput;
     }
 
-    int rowsDecoded;
-    SkCodec::Result result;
     switch (WebPIUpdate(idec, frame.fragment.bytes, frame.fragment.size)) {
         case VP8_STATUS_OK:
-            rowsDecoded = dstInfo.height();
-            result = kSuccess;
-            break;
+            return kSuccess;
         case VP8_STATUS_SUSPENDED:
-            WebPIDecGetRGB(idec, rowsDecodedPtr, nullptr, nullptr, nullptr);
-            rowsDecoded = *rowsDecodedPtr;
-            result = kIncompleteInput;
-            break;
+            WebPIDecGetRGB(idec, rowsDecoded, nullptr, nullptr, nullptr);
+            return kIncompleteInput;
         default:
             return kInvalidInput;
     }
-
-    if (colorXform) {
-        SkAlphaType xformAlphaType = select_alpha_xform(dstInfo.alphaType(),
-                                                        this->getInfo().alphaType());
-
-        uint32_t* src = (uint32_t*) config.output.u.RGBA.rgba;
-        size_t srcRowBytes = config.output.u.RGBA.stride;
-        for (int y = 0; y < rowsDecoded; y++) {
-            colorXform->apply(dst, src, dstInfo.width(), dstInfo.colorType(), xformAlphaType);
-            dst = SkTAddOffset<void>(dst, rowBytes);
-            src = SkTAddOffset<uint32_t>(src, srcRowBytes);
-        }
-    }
-
-    return result;
 }
 
 SkWebpCodec::SkWebpCodec(int width, int height, const SkEncodedInfo& info,