Fix the size of video textures uploaded to WebGL.

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

Index: third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
diff --git a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
index 42972294f3d78d5904bd7dc548708e646f034219..0a8867d688f78d01265dcc01fdcbae31dc319c57 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
+++ b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
@@ -5217,9 +5217,17 @@ void WebGLRenderingContextBase::texImageHelperHTMLVideoElement(
     // Go through the fast path doing a GPU-GPU textures copy without a readback
     // to system memory if possible.  Otherwise, it will fall back to the normal
     // SW path.
-    if (video->copyVideoTextureToPlatformTexture(
-            contextGL(), texture->object(), internalformat, type,
-            m_unpackPremultiplyAlpha, m_unpackFlipY)) {
+
+    // Note that neither
+    // HTMLVideoElement::copyVideoTextureToPlatformTexture nor
+    // ImageBuffer::copyToPlatformTexture allocate the destination texture
+    // any more.
+    texImage2DBase(target, level, internalformat, video->videoWidth(),
+                   video->videoHeight(), 0, format, type, nullptr);
+
+    if (video->copyVideoTextureToPlatformTexture(contextGL(), texture->object(),
+                                                 m_unpackPremultiplyAlpha,
+                                                 m_unpackFlipY)) {
       return;
     }
 
@@ -5243,11 +5251,6 @@ void WebGLRenderingContextBase::texImageHelperHTMLVideoElement(
         // This is a straight GPU-GPU copy, any necessary color space conversion
         // was handled in the paintCurrentFrameInContext() call.
 
-        // Note that copyToPlatformTexture no longer allocates the destination
-        // texture.
-        texImage2DBase(target, level, internalformat, video->videoWidth(),
-                       video->videoHeight(), 0, format, type, nullptr);
-
         if (imageBuffer->copyToPlatformTexture(
                 functionIDToSnapshotReason(functionID), contextGL(),
                 texture->object(), internalformat, type, level,