Don't crash when an image fails to decode.

Source/platform/graphics/BitmapImageTest.cpp

 /*
  * Copyright (c) 2013, 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 88 matching lines @@
         for (size_t i = 0; i < decodedFramesCount(); ++i)
             size += frameDecodedSize(i);
         return size;
     }
 
     void advanceAnimation()
     {
         m_image->advanceAnimation(0);
     }
 
+    PassRefPtr<Image> imageForDefaultFrame()
+    {
+        return m_image->imageForDefaultFrame();
+    }
+
 protected:
     virtual void SetUp() OVERRIDE
     {
         DeferredImageDecoder::setEnabled(false);
         m_image = BitmapImage::create(&m_imageObserver);
     }
 
     FakeImageObserver m_imageObserver;
     RefPtr<BitmapImage> m_image;
 };
@@ skipping 104 matching lines @@
 
     destroyDecodedData(true);
     resetDecoder();
 
     loadImage("/LayoutTests/fast/images/resources/test.webp");
     EXPECT_EQ(1u, decodedFramesCount());
     EXPECT_EQ(65536u, decodedSize());
     EXPECT_FALSE(m_image->hasColorProfile());
 }
 
+TEST_F(BitmapImageTest, icoHasWrongFrameDimensions)
+{
+    loadImage("/LayoutTests/fast/images/resources/wrong-frame-dimensions.ico");
+    // This call would cause crash without fix for 408026
+    imageForDefaultFrame();
+}
+
 #endif // USE(QCMSLIB)
 
 } // namespace blink