add runtime option to provide data->imagegenerator factory

BUG=skia:

Review URL: https://codereview.chromium.org/1229933003

5 files changed, 30 insertions, 8 deletions

diff --git a/src/core/SkImageGenerator.cpp b/src/core/SkImageGenerator.cpp
index b4a3fc21c8..7da4d40b0c 100644
--- a/src/core/SkImageGenerator.cpp
+++ b/src/core/SkImageGenerator.cpp
@@ -130,3 +130,29 @@ bool SkImageGenerator::onGetPixels(const SkImageInfo& info, void* dst, size_t rb
     return false;
 }
 #endif
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+#include "SkGraphics.h"
+
+static SkGraphics::ImageGeneratorFromEncodedFactory gImageGeneratorFromEncodedFactory;
+
+SkGraphics::ImageGeneratorFromEncodedFactory SkGraphics::GetImageGeneratorFromEncodedFactory() {
+    return gImageGeneratorFromEncodedFactory;
+}
+
+void SkGraphics::SetImageGeneratorFromEncodedFactory(ImageGeneratorFromEncodedFactory factory) {
+    gImageGeneratorFromEncodedFactory = factory;
+}
+
+SkImageGenerator* SkImageGenerator::NewFromEncoded(SkData* data) {
+    if (NULL == data) {
+        return NULL;
+    }
+    if (gImageGeneratorFromEncodedFactory) {
+        if (SkImageGenerator* generator = gImageGeneratorFromEncodedFactory(data)) {
+            return generator;
+        }
+    }
+    return SkImageGenerator::NewFromEncodedImpl(data);
+}
diff --git a/src/image/SkImage.cpp b/src/image/SkImage.cpp
index e8a3ead2b1..ff0b8c9819 100644
--- a/src/image/SkImage.cpp
+++ b/src/image/SkImage.cpp
@@ -76,7 +76,7 @@ SkImage* SkImage::NewFromEncoded(SkData* encoded, const SkIRect* subset) {
     if (NULL == encoded || 0 == encoded->size()) {
         return NULL;
     }
-    SkImageGenerator* generator = SkImageGenerator::NewFromData(encoded);
+    SkImageGenerator* generator = SkImageGenerator::NewFromEncoded(encoded);
     return generator ? SkImage::NewFromGenerator(generator, subset) : NULL;
 }
 
diff --git a/src/lazy/SkDiscardablePixelRef.cpp b/src/lazy/SkDiscardablePixelRef.cpp
index 19bfc8ccc7..4f9178e6e1 100644
--- a/src/lazy/SkDiscardablePixelRef.cpp
+++ b/src/lazy/SkDiscardablePixelRef.cpp
@@ -150,6 +150,6 @@ bool SkInstallDiscardablePixelRef(SkImageGenerator* generator, SkBitmap* dst) {
 }
 
 bool SkInstallDiscardablePixelRef(SkData* encoded, SkBitmap* dst) {
-    SkImageGenerator* generator = SkImageGenerator::NewFromData(encoded);
+    SkImageGenerator* generator = SkImageGenerator::NewFromEncoded(encoded);
     return generator ? SkInstallDiscardablePixelRef(generator, NULL, dst, NULL) : false;
 }
diff --git a/src/ports/SkImageGenerator_none.cpp b/src/ports/SkImageGenerator_none.cpp
index 78d408aa35..c0126cae79 100644
--- a/src/ports/SkImageGenerator_none.cpp
+++ b/src/ports/SkImageGenerator_none.cpp
@@ -7,6 +7,6 @@
 
 #include "SkImageGenerator.h"
 
-SkImageGenerator* SkImageGenerator::NewFromData(SkData*) {
+SkImageGenerator* SkImageGenerator::NewFromEncodedImpl(SkData*) {
     return NULL;
 }
diff --git a/src/ports/SkImageGenerator_skia.cpp b/src/ports/SkImageGenerator_skia.cpp
index f972253306..1dbc9a5f33 100644
--- a/src/ports/SkImageGenerator_skia.cpp
+++ b/src/ports/SkImageGenerator_skia.cpp
@@ -108,11 +108,7 @@ private:
     typedef SkImageGenerator INHERITED;
 };
 
-SkImageGenerator* SkImageGenerator::NewFromData(SkData* data) {
-    if (NULL == data) {
-        return NULL;
-    }
-
+SkImageGenerator* SkImageGenerator::NewFromEncodedImpl(SkData* data) {
     SkMemoryStream stream(data->data(), data->size(), false);
     SkImageDecoder* decoder = SkImageDecoder::Factory(&stream);
     if (NULL == decoder) {