initial import of Chrome's trace_event into skia framework

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/ARGB32_Clamp_Bilinear_BitmapShader.h',
@@ skipping 165 matching lines @@
         '<(skia_src_path)/core/SkStrokeRec.cpp',
         '<(skia_src_path)/core/SkStrokerPriv.cpp',
         '<(skia_src_path)/core/SkStrokerPriv.h',
         '<(skia_src_path)/core/SkTemplatesPriv.h',
         '<(skia_src_path)/core/SkTextFormatParams.h',
         '<(skia_src_path)/core/SkTileGrid.cpp',
         '<(skia_src_path)/core/SkTileGrid.h',
         '<(skia_src_path)/core/SkTileGridPicture.cpp',
         '<(skia_src_path)/core/SkTLList.h',
         '<(skia_src_path)/core/SkTLS.cpp',
+        '<(skia_src_path)/core/SkTraceEvent.h',
         '<(skia_src_path)/core/SkTSearch.cpp',
         '<(skia_src_path)/core/SkTSort.h',
         '<(skia_src_path)/core/SkTypeface.cpp',
         '<(skia_src_path)/core/SkTypefaceCache.cpp',
         '<(skia_src_path)/core/SkTypefaceCache.h',
         '<(skia_src_path)/core/SkUnPreMultiply.cpp',
         '<(skia_src_path)/core/SkUtils.cpp',
         '<(skia_src_path)/core/SkValidatingReadBuffer.cpp',
         '<(skia_src_path)/core/SkWriter32.cpp',
         '<(skia_src_path)/core/SkXfermode.cpp',
@@ skipping 158 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',
     ],
 }