Remove OS(WINCE) as blink and chromium does not support WinCe.

Source/core/platform/graphics/BitmapImage.cpp

 /*
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2008 Apple 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 542 matching lines @@
     // while trying to skip frames we hit the last frame and thus had to stop.
     if (skippingFrames != advancedAnimation)
         imageObserver()->animationAdvanced(this);
     return advancedAnimation;
 }
 
 bool BitmapImage::mayFillWithSolidColor()
 {
     if (!m_checkedForSolidColor && frameCount() > 0) {
         checkForSolidColor();
-        // WINCE PORT: checkForSolidColor() doesn't set m_checkedForSolidColor until
-        // it gets enough information to make final decision.
-#if !OS(WINCE)
         ASSERT(m_checkedForSolidColor);
-#endif
     }
     return m_isSolidColor && !m_currentFrame;
 }
 
 Color BitmapImage::solidColor() const
 {
     return m_solidColor;
 }
 
 void BitmapImage::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, PlatformMemoryTypes::Image);
     memoryObjectInfo->setClassName("BitmapImage");
     Image::reportMemoryUsage(memoryObjectInfo);
     info.addMember(m_source, "source");
     info.addMember(m_frameTimer, "frameTimer");
     info.addMember(m_frames, "frames");
 }
 
 void FrameData::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, PlatformMemoryTypes::Image);
     memoryObjectInfo->setClassName("FrameData");
     info.addMember(m_frame, "frame", WTF::RetainingPointer);
 }
 
 }