Upgrade blink side ReadPixels size validation to consider ES3 pack parameters.

third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp

Index: third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
diff --git a/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp b/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
index 9478f11f692f61e4fbb2de8e7cc50f06fa6f1954..dc6b2750e4e5492f44d137fed276aa0ad3fc29d4 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
+++ b/third_party/WebKit/Source/modules/webgl/WebGL2RenderingContextBase.cpp
@@ -3443,4 +3443,26 @@ const WebGLSamplerState* WebGL2RenderingContextBase::getTextureUnitSamplerState(
     return WebGLRenderingContextBase::getTextureUnitSamplerState(target, unit);
 }
 
+WebGLImageConversion::PixelStoreParams WebGL2RenderingContextBase::getPackPixelStoreParams()
+{
+    WebGLImageConversion::PixelStoreParams params;
+    params.alignment = m_packAlignment;
+    params.rowLength = m_packRowLength;
+    params.skipPixels = m_packSkipPixels;
+    params.skipRows = m_packSkipRows;
+    return params;
+}
+
+WebGLImageConversion::PixelStoreParams WebGL2RenderingContextBase::getUnpackPixelStoreParams()
+{
+    WebGLImageConversion::PixelStoreParams params;
+    params.alignment = m_unpackAlignment;
+    params.rowLength = m_unpackRowLength;
+    params.imageHeight = m_unpackImageHeight;
+    params.skipPixels = m_unpackSkipPixels;
+    params.skipRows = m_unpackSkipRows;
+    params.skipImages = m_unpackSkipImages;
+    return params;
+}
+
 } // namespace blink