Remove redundant code for getMappedPointer in PixelBuffer

b/29755121

Change-Id: I6cd5bbe11a53bc5e1cd421671d3d9aa89591d886
diff --git a/libs/hwui/PixelBuffer.h b/libs/hwui/PixelBuffer.h
index bbef36b..9536bc8 100644
--- a/libs/hwui/PixelBuffer.h
+++ b/libs/hwui/PixelBuffer.h
@@ -99,12 +99,6 @@
     }
 
     /**
-     * Returns the currently mapped pointer. Returns NULL if the buffer
-     * is not mapped.
-     */
-    virtual uint8_t* getMappedPointer() const = 0;
-
-    /**
      * Upload the specified rectangle of this pixel buffer as a
      * GL_TEXTURE_2D texture. Calling this method will trigger
      * an unmap() if necessary.
@@ -199,8 +193,7 @@
     /**
      * Unmaps this buffer, if needed. After the buffer is unmapped,
      * the pointer previously returned by map() becomes invalid and
-     * should not be used. After calling this method, getMappedPointer()
-     * will always return NULL.
+     * should not be used.
      */
     virtual void unmap() = 0;