expose generalized imagecache key

gyp/core.gypi

 # Include this gypi to include all 'core' files
 # The parent gyp/gypi file must define
 #       'skia_src_path'     e.g. skia/trunk/src
 #       'skia_include_path' e.g. skia/trunk/include
 #
 # The skia build defines these in common_variables.gypi
 #
 {
     'sources': [
         '<(skia_src_path)/core/SkAAClip.cpp',
         '<(skia_src_path)/core/SkAnnotation.cpp',
         '<(skia_src_path)/core/SkAdvancedTypefaceMetrics.cpp',
         '<(skia_src_path)/core/SkAlphaRuns.cpp',
         '<(skia_src_path)/core/SkAntiRun.h',
         '<(skia_src_path)/core/SkBBHFactory.cpp',
         '<(skia_src_path)/core/SkBBoxHierarchy.h',
         '<(skia_src_path)/core/SkBBoxRecord.cpp',
         '<(skia_src_path)/core/SkBBoxRecord.h',
         '<(skia_src_path)/core/SkBBoxHierarchyRecord.cpp',
         '<(skia_src_path)/core/SkBBoxHierarchyRecord.h',
         '<(skia_src_path)/core/SkBitmap.cpp',
+        '<(skia_src_path)/core/SkBitmapCache.cpp',
         '<(skia_src_path)/core/SkBitmapDevice.cpp',
         '<(skia_src_path)/core/SkBitmapFilter.h',
         '<(skia_src_path)/core/SkBitmapFilter.cpp',
         '<(skia_src_path)/core/SkBitmapHeap.cpp',
         '<(skia_src_path)/core/SkBitmapHeap.h',
         '<(skia_src_path)/core/SkBitmapProcShader.cpp',
         '<(skia_src_path)/core/SkBitmapProcShader.h',
         '<(skia_src_path)/core/SkBitmapProcState.cpp',
         '<(skia_src_path)/core/SkBitmapProcState.h',
         '<(skia_src_path)/core/SkBitmapProcState_matrix.h',
@@ skipping 339 matching lines @@
         '<(skia_src_path)/pathops/SkPathOpsPoint.h',
         '<(skia_src_path)/pathops/SkPathOpsQuad.h',
         '<(skia_src_path)/pathops/SkPathOpsRect.h',
         '<(skia_src_path)/pathops/SkPathOpsTriangle.h',
         '<(skia_src_path)/pathops/SkPathOpsTypes.h',
         '<(skia_src_path)/pathops/SkPathWriter.h',
         '<(skia_src_path)/pathops/SkQuarticRoot.h',
         '<(skia_src_path)/pathops/SkReduceOrder.h',
     ],
 }