Make BitmapRegionDecoder succeed on invalid requests

include/codec/SkAndroidCodec.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 SkAndroidCodec_DEFINED
 #define SkAndroidCodec_DEFINED
 
@@ skipping 35 matching lines @@
 
 
     const SkImageInfo& getInfo() const { return fInfo; }
 
     /**
      *  Format of the encoded data.
      */
     SkEncodedFormat getEncodedFormat() const { return this->onGetEncodedFormat(); }
 
     /**
+     *  @param requestedColorType Color type requested by the client

[djsollen, 2015/12/11 13:49:25]

When doxygen formats this comment this won't look quite right.  Each method
should have a description, which it looks like you put mostly in the @return
annotation.  I would just delete the @return and make those the main body of the
comment.

[msarett, 2015/12/11 14:17:53]

Done.  Also changing the comment to reflect that we default to the color type
recommended by the codec.

+     *
+     *  @return If it is possible to decode to requestedColorType, this returns
+     *          requestedColorType.  Otherwise, this returns kN32_SkColorType.
+     */
+    SkColorType computeOutputColorType(SkColorType requestedColorType);
+
+    /**
+     *  @param requestedUnpremul  Indicates if the client requested
+     *                            unpremultiplied output
+     *
+     *  @return Returns the appropriate alpha type to decode to.  If the image
+     *          has alpha, the value of requestedUnpremul will be honored.
+     */
+    SkAlphaType computeOutputAlphaType(bool requestedUnpremul);
+
+    /**
      *  Returns the dimensions of the scaled output image, for an input
      *  sampleSize.
      *
      *  When the sample size divides evenly into the original dimensions, the
      *  scaled output dimensions will simply be equal to the original
      *  dimensions divided by the sample size.
      *
      *  When the sample size does not divide even into the original
      *  dimensions, the codec may round up or down, depending on what is most
      *  efficient to decode.
@@ skipping 155 matching lines @@
     virtual SkCodec::Result onGetAndroidPixels(const SkImageInfo& info, void* pixels,
             size_t rowBytes, const AndroidOptions& options) = 0;
 
 private:
 
     // This will always be a reference to the info that is contained by the
     // embedded SkCodec.
     const SkImageInfo& fInfo;
 };
 #endif // SkAndroidCodec_DEFINED