Implementing directional selection strategy in Blink.

Source/core/core.gypi

 {
     'includes': [
         'core_generated.gypi',
     ],
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/Animation.idl',
             'animation/AnimationEffect.idl',
             'animation/AnimationNode.idl',
@@ skipping 1292 matching lines @@
             'editing/EditingBehavior.h',
             'editing/EditingStrategy.cpp',
             'editing/EditingStrategy.h',
             'editing/EditingStyle.cpp',
             'editing/Editor.cpp',
             'editing/EditorCommand.cpp',
             'editing/EditorKeyBindings.cpp',
             'editing/FormatBlockCommand.cpp',
             'editing/FormatBlockCommand.h',
             'editing/FrameSelection.cpp',
+            'editing/GranularityStrategy.cpp',
             'editing/HTMLInterchange.cpp',
             'editing/IndentOutdentCommand.cpp',
             'editing/IndentOutdentCommand.h',
             'editing/InputMethodController.cpp',
             'editing/InputMethodController.h',
             'editing/InsertIntoTextNodeCommand.cpp',
             'editing/InsertIntoTextNodeCommand.h',
             'editing/InsertLineBreakCommand.cpp',
             'editing/InsertLineBreakCommand.h',
             'editing/InsertListCommand.cpp',
@@ skipping 2511 matching lines @@
             'paint/LayerClipRecorderTest.cpp',
             'paint/LayoutObjectDrawingRecorderTest.cpp',
             'paint/TextPainterTest.cpp',
             'streams/ReadableStreamReaderTest.cpp',
             'streams/ReadableStreamTest.cpp',
             'testing/PrivateScriptTestTest.cpp',
             'xml/parser/SharedBufferReaderTest.cpp',
         ],
     }
 }