Merge 117191 - Assertion failure running Mozilla's WebGL performance regression tests

Source/WebCore/platform/graphics/cg/GraphicsContext3DCG.cpp

 /*
  * Copyright (C) 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 222 matching lines @@
     }
     SourceDataFormat srcDataFormat = getSourceDataFormat(componentsPerPixel, alphaFormat, bitsPerComponent == 16, bigEndianSource);
     if (srcDataFormat == SourceFormatNumFormats)
         return false;
 
     RetainPtr<CFDataRef> pixelData;
     pixelData.adoptCF(CGDataProviderCopyData(CGImageGetDataProvider(cgImage)));
     if (!pixelData)
         return false;
     const UInt8* rgba = CFDataGetBytePtr(pixelData.get());
-    outputVector.resize(width * height * 4);
+
+    unsigned int packedSize;
+    // Output data is tightly packed (alignment == 1).
+    if (computeImageSizeInBytes(format, type, width, height, 1, &packedSize, 0) != GraphicsContext3D::NO_ERROR)
+        return false;
+    outputVector.resize(packedSize);
+
     unsigned int srcUnpackAlignment = 0;
     size_t bytesPerRow = CGImageGetBytesPerRow(cgImage);
     unsigned int padding = bytesPerRow - bitsPerPixel / 8 * width;
     if (padding) {
         srcUnpackAlignment = padding + 1;
         while (bytesPerRow % srcUnpackAlignment)
             ++srcUnpackAlignment;
     }
     bool rt = packPixels(rgba, srcDataFormat, width, height, srcUnpackAlignment,
                          format, type, neededAlphaOp, outputVector.data());
@@ skipping 17 matching lines @@
     CGContextSaveGState(context);
     CGContextSetBlendMode(context, kCGBlendModeCopy);
     CGContextSetInterpolationQuality(context, kCGInterpolationNone);
     CGContextDrawImage(context, rect, cgImage.get());
     CGContextRestoreGState(context);
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEBGL)