Fix ImageDecoder::frameIsCompleteAtIndex - fully received instead of decoded.

third_party/WebKit/Source/platform/image-decoders/webp/WEBPImageDecoder.cpp

Index: third_party/WebKit/Source/platform/image-decoders/webp/WEBPImageDecoder.cpp
diff --git a/third_party/WebKit/Source/platform/image-decoders/webp/WEBPImageDecoder.cpp b/third_party/WebKit/Source/platform/image-decoders/webp/WEBPImageDecoder.cpp
index fae908a78e567ec303b4b967a767735cffe0861c..d347c85b1ab32a9ce7dc45f84aa7bcf71bd3adb8 100644
--- a/third_party/WebKit/Source/platform/image-decoders/webp/WEBPImageDecoder.cpp
+++ b/third_party/WebKit/Source/platform/image-decoders/webp/WEBPImageDecoder.cpp
@@ -166,14 +166,15 @@ int WEBPImageDecoder::repetitionCount() const
     return failed() ? cAnimationLoopOnce : m_repetitionCount;
 }
 
-bool WEBPImageDecoder::frameIsCompleteAtIndex(size_t index) const
+bool WEBPImageDecoder::frameIsFullyReceivedAtIndex(size_t index) const
 {
-    if (!m_demux || m_demuxState <= WEBP_DEMUX_PARSING_HEADER)
-        return false;
+    DCHECK(haveUpdatedFrameCount());
     if (!(m_formatFlags & ANIMATION_FLAG))
-        return ImageDecoder::frameIsCompleteAtIndex(index);
-    bool frameIsLoadedAtIndex = index < m_frameBufferCache.size();
-    return frameIsLoadedAtIndex;
+        return ImageDecoder::frameIsFullyReceivedAtIndex(index);
+
+    // Multi-frame WebP frame gets added to m_frameBufferCache through
+    // initializeNewFrame() only when the frame data is fully received.
+    return index < m_frameBufferCache.size();
 }
 
 float WEBPImageDecoder::frameDurationAtIndex(size_t index) const