Fix utils.gyp missing file

gyp/utils.gyp

 # Gyp for utils.
 {
   'targets': [
     {
       'target_name': 'utils',
       'product_name': 'skia_utils',
       'type': 'static_library',
       'standalone_static_library': 1,
       'dependencies': [
         'core.gyp:*',
@@ skipping 24 matching lines @@
 
         '../include/utils/SkBoundaryPatch.h',
         '../include/utils/SkFrontBufferedStream.h',
         '../include/utils/SkCamera.h',
         '../include/utils/SkCanvasStateUtils.h',
         '../include/utils/SkCubicInterval.h',
         '../include/utils/SkCullPoints.h',
         '../include/utils/SkDebugUtils.h',
         '../include/utils/SkDeferredCanvas.h',
         '../include/utils/SkDumpCanvas.h',
-        '../include/utils/SkGatherPixelRefsAndRects.h',
         '../include/utils/SkInterpolator.h',
         '../include/utils/SkLayer.h',
         '../include/utils/SkMatrix44.h',
         '../include/utils/SkMeshUtils.h',
         '../include/utils/SkNinePatch.h',
         '../include/utils/SkNWayCanvas.h',
         '../include/utils/SkNullCanvas.h',
         '../include/utils/SkParse.h',
         '../include/utils/SkParsePaint.h',
         '../include/utils/SkParsePath.h',
@@ skipping 15 matching lines @@
         '../src/utils/SkCamera.cpp',
         '../src/utils/SkCanvasStack.h',
         '../src/utils/SkCanvasStack.cpp',
         '../src/utils/SkCanvasStateUtils.cpp',
         '../src/utils/SkCubicInterval.cpp',
         '../src/utils/SkCullPoints.cpp',
         '../src/utils/SkDeferredCanvas.cpp',
         '../src/utils/SkDumpCanvas.cpp',
         '../src/utils/SkFloatUtils.h',
         '../src/utils/SkGatherPixelRefsAndRects.cpp',
+        '../src/utils/SkGatherPixelRefsAndRects.h',
         '../src/utils/SkInterpolator.cpp',
         '../src/utils/SkLayer.cpp',
         '../src/utils/SkMatrix44.cpp',
         '../src/utils/SkMD5.cpp',
         '../src/utils/SkMD5.h',
         '../src/utils/SkMeshUtils.cpp',
         '../src/utils/SkNinePatch.cpp',
         '../src/utils/SkNoSaveLayerCanvas.h',
         '../src/utils/SkNWayCanvas.cpp',
         '../src/utils/SkNullCanvas.cpp',
@@ skipping 133 matching lines @@
         }],
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           '../include/utils',
         ],
       },
     },
   ],
 }