move colorshader into its own .cpp, add color4f variant

gyp/core.gypi

 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 # 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
@@ skipping 55 matching lines @@
         '<(skia_src_path)/core/SkCanvas.cpp',
         '<(skia_src_path)/core/SkCanvasPriv.h',
         '<(skia_src_path)/core/SkChecksum.cpp',
         '<(skia_src_path)/core/SkChunkAlloc.cpp',
         '<(skia_src_path)/core/SkClipStack.cpp',
         '<(skia_src_path)/core/SkColor.cpp',
         '<(skia_src_path)/core/SkColorFilter.cpp',
         '<(skia_src_path)/core/SkColorFilterShader.cpp',
         '<(skia_src_path)/core/SkColorMatrixFilterRowMajor255.cpp',
         '<(skia_src_path)/core/SkColorMatrixFilterRowMajor255.h',
+        '<(skia_src_path)/core/SkColorShader.cpp',
         '<(skia_src_path)/core/SkColorShader.h',
         '<(skia_src_path)/core/SkColorSpace.cpp',
         '<(skia_src_path)/core/SkColorSpace.h',
         '<(skia_src_path)/core/SkColorTable.cpp',
         '<(skia_src_path)/core/SkComposeShader.cpp',
         '<(skia_src_path)/core/SkConfig8888.cpp',
         '<(skia_src_path)/core/SkConfig8888.h',
         '<(skia_src_path)/core/SkConvolver.cpp',
         '<(skia_src_path)/core/SkConvolver.h',
         '<(skia_src_path)/core/SkCoreBlitters.h',
@@ skipping 406 matching lines @@
         '<(skia_src_path)/pathops/SkPathOpsLine.h',
         '<(skia_src_path)/pathops/SkPathOpsPoint.h',
         '<(skia_src_path)/pathops/SkPathOpsQuad.h',
         '<(skia_src_path)/pathops/SkPathOpsRect.h',
         '<(skia_src_path)/pathops/SkPathOpsTSect.h',
         '<(skia_src_path)/pathops/SkPathOpsTypes.h',
         '<(skia_src_path)/pathops/SkPathWriter.h',
         '<(skia_src_path)/pathops/SkReduceOrder.h',
     ],
 }