Revert of remove colorfilter native-565 support. complicating w/ no real value.

include/core/SkColorFilter.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkColorFilter_DEFINED
 #define SkColorFilter_DEFINED
 
@@ skipping 50 matching lines @@
      */
     virtual bool asComponentTable(SkBitmap* table) const;
 
     /** Called with a scanline of colors, as if there was a shader installed.
         The implementation writes out its filtered version into result[].
         Note: shader and result may be the same buffer.
         @param src      array of colors, possibly generated by a shader
         @param count    the number of entries in the src[] and result[] arrays
         @param result   written by the filter
     */
-    virtual void filterSpan(const SkPMColor src[], int count, SkPMColor result[]) const = 0;
+    virtual void filterSpan(const SkPMColor src[], int count,
+                            SkPMColor result[]) const = 0;
+    /** Called with a scanline of colors, as if there was a shader installed.
+        The implementation writes out its filtered version into result[].
+        Note: shader and result may be the same buffer.
+        @param src      array of colors, possibly generated by a shader
+        @param count    the number of entries in the src[] and result[] arrays
+        @param result   written by the filter
+    */
+    virtual void filterSpan16(const uint16_t shader[], int count,
+                              uint16_t result[]) const;
 
     enum Flags {
-        /** If set the filter methods will not change the alpha channel of the colors.
+        /** If set the filter methods will not change the alpha channel of the
+            colors.
         */
         kAlphaUnchanged_Flag = 0x01,
+        /** If set, this subclass implements filterSpan16(). If this flag is
+            set, then kAlphaUnchanged_Flag must also be set.
+        */
+        kHasFilter16_Flag    = 0x02
     };
 
-    /** Returns the flags for this filter. Override in subclasses to return custom flags.
+    /** Returns the flags for this filter. Override in subclasses to return
+        custom flags.
     */
     virtual uint32_t getFlags() const { return 0; }
 
     /**
      *  If this subclass can optimally createa composition with the inner filter, return it as
      *  a new filter (which the caller must unref() when it is done). If no such optimization
      *  is known, return NULL.
      *
      *  e.g. result(color) == this_filter(inner(color))
      */
@@ skipping 66 matching lines @@
      *
      *  e.g. compose(filter, compose(compose(filter, filter), filter)) --> 4
      */
     virtual int privateComposedFilterCount() const { return 1; }
     friend class SkComposeColorFilter;
 
     typedef SkFlattenable INHERITED;
 };
 
 #endif