DM: read image files without an extra copy

include/core/SkStream.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 SkStream_DEFINED
 #define SkStream_DEFINED
 
@@ skipping 345 matching lines @@
 public:
     SK_DECLARE_INST_COUNT(SkFILEWStream)
 
     SkFILEWStream(const char path[]);
     virtual ~SkFILEWStream();
 
     /** Returns true if the current path could be opened.
     */
     bool isValid() const { return fFILE != NULL; }
 
+    size_t bytesWritten() const;

[reed1, 2014/03/05 13:23:46]

We have this on several WStreams. I wonder if its valuable to make it virtual on
SkWStream itself, so clients can rely on it... Not meant to hold-up this CL.

     virtual bool write(const void* buffer, size_t size) SK_OVERRIDE;
     virtual void flush() SK_OVERRIDE;
 
 private:
     SkFILE* fFILE;
 
     typedef SkWStream INHERITED;
 };
 
 class SkMemoryWStream : public SkWStream {
@@ skipping 68 matching lines @@
     virtual void newline() SK_OVERRIDE;
 
 private:
     typedef SkWStream INHERITED;
 };
 
 // for now
 typedef SkFILEStream SkURLStream;
 
 #endif