Consolidate SkCodec functions for handling rewind

src/codec/SkBmpCodec.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef SkBmpCodec_DEFINED
 #define SkBmpCodec_DEFINED
 
 #include "SkCodec.h"
@@ skipping 45 matching lines @@
     SkEncodedFormat onGetEncodedFormat() const override { return kBMP_SkEncodedFormat; }
 
     /*
      * Read enough of the stream to initialize the SkBmpCodec. Returns a bool
      * representing success or failure. If it returned true, and codecOut was
      * not NULL, it will be set to a new SkBmpCodec.
      * Does *not* take ownership of the passed in SkStream.
      */
     static bool ReadHeader(SkStream*, bool inIco, SkCodec** codecOut);
 
+    bool onRewind() override;
+
     /*
-     * Rewinds the image stream if necessary
+     * Returns whether this BMP is part of an ICO image.
      */
-    bool handleRewind(bool inIco);
+    bool inIco() const {

[scroggo_chromium, 2015/08/11 16:29:42]

This split follows the convention we follow for public functions:

public:

function() {
  return this->onVirtualFunction();
}

protected:

virtual onVirtualFunction();

Maybe this isn't necessary here, since inIco() does not need to be made public?

[msarett, 2015/08/12 13:38:46]

I don't feel strongly on this.  Looks fine to me.

+        return this->onInIco();
+    }
+
+    virtual bool onInIco() const {
+        return false;
+    }
 
     /*
      * Get the destination row to start filling from
      * Used to fill the remainder of the image on incomplete input for bmps
      * This is tricky since bmps may be kTopDown or kBottomUp.  For kTopDown,
      * we start filling from where we left off, but for kBottomUp we start
      * filling at the top of the image.
      */
     void* getDstStartRow(void* dst, size_t dstRowBytes, int32_t y) const;
 
@@ skipping 16 matching lines @@
      */
     static SkCodec* NewFromStream(SkStream*, bool inIco);
 
     const uint16_t fBitsPerPixel;
     const RowOrder fRowOrder;
 
     typedef SkCodec INHERITED;
 };
 
 #endif