Remove SkImageRef and related functionality.

gyp/public_headers.gypi

 # Include this gypi to include all public header files that exist in the
 # include directory.
 #
 # The list is computed by running 'find include -name *.h' in the root dir of
 # the project.
 #
 {
   'variables': {
     'header_filenames': [
       'pdf/SkPDFDevice.h',
@@ skipping 44 matching lines @@
       'gpu/GrColor.h',
       'gpu/GrGlyph.h',
       'gpu/GrBackendEffectFactory.h',
       'gpu/GrContextFactory.h',
       'gpu/GrRenderTarget.h',
       'gpu/GrSurface.h',
       'gpu/GrTypesPriv.h',
       'config/sk_stdint.h',
       'config/SkUserConfig.h',
       'pipe/SkGPipe.h',
-      'images/SkImageRef.h',
       'images/SkMovie.h',
       'images/SkPageFlipper.h',
       'images/SkForceLinking.h',
-      'images/SkImageRef_GlobalPool.h',
-      'images/SkImages.h',
       'effects/SkMorphologyImageFilter.h',
       'effects/Sk2DPathEffect.h',
       'effects/SkXfermodeImageFilter.h',
       'effects/SkAlphaThresholdFilter.h',
       'effects/SkArithmeticMode.h',
       'effects/SkMergeImageFilter.h',
       'effects/SkPerlinNoiseShader.h',
       'effects/SkLerpXfermode.h',
       'effects/SkLumaColorFilter.h',
       'effects/SkRectShaderImageFilter.h',
@@ skipping 202 matching lines @@
       'views/unix/XkeysToSkKeys.h',
       'views/SkKey.h',
       'views/SkView.h',
       'views/SkOSMenu.h',
       'views/SkOSWindow_Unix.h',
       'views/SkWidget.h',
       'views/SkOSWindow_Win.h',
     ],
   },
 }