Canvas.toDataURL to use SkBitmap::readPixels to avoid uninitialized memory

Source/platform/image-encoders/skia/WEBPImageEncoder.cpp

Index: Source/platform/image-encoders/skia/WEBPImageEncoder.cpp
diff --git a/Source/platform/image-encoders/skia/WEBPImageEncoder.cpp b/Source/platform/image-encoders/skia/WEBPImageEncoder.cpp
index 3f00f6797e6132f1ceeb86dd3574aac64f9b9cf1..e82e4bffa23940a81d8f68219ebb6a53e62eb6e9 100644
--- a/Source/platform/image-encoders/skia/WEBPImageEncoder.cpp
+++ b/Source/platform/image-encoders/skia/WEBPImageEncoder.cpp
@@ -53,9 +53,8 @@ static bool rgbPictureImport(const unsigned char* pixels, bool premultiplied, We
 
     // Write the RGB pixels to an rgb data buffer, alpha premultiplied, then import the rgb data.
 
-    Vector<unsigned char> rgb;
     size_t pixelCount = picture->height * picture->width;
-    rgb.reserveInitialCapacity(pixelCount * 3);
+    Vector<unsigned char> rgb(pixelCount * 3);
 

[Noel Gordon, 2015/07/21 00:48:36]

Overall patch seems fine, but just to confirm, there was a perf hit here? 

     for (unsigned char* data = rgb.data(); pixelCount-- > 0; pixels += 4) {
         unsigned char alpha = pixels[3];