Set sRGB flag for PNGs with an sRGB chunk

src/codec/SkPngCodec.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
 #include "SkColorTable.h"
@@ skipping 310 matching lines @@
         default:
             // All the color types have been covered above.
             SkASSERT(false);
     }
 
     int numberPasses = png_set_interlace_handling(png_ptr);
     if (numberPassesPtr) {
         *numberPassesPtr = numberPasses;
     }
 
-    // FIXME: Also need to check for sRGB ( https://bug.skia.org/3471 ).
+    SkColorProfileType profileType = kLinear_SkColorProfileType;
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sRGB)) {
+        profileType = kSRGB_SkColorProfileType;
+    }
 
     if (imageInfo) {
-        *imageInfo = SkImageInfo::Make(origWidth, origHeight, colorType, alphaType);
+        *imageInfo = SkImageInfo::Make(origWidth, origHeight, colorType, alphaType, profileType);
     }
     autoClean.detach();
     if (png_ptrp) {
         *png_ptrp = png_ptr;
     }
     if (info_ptrp) {
         *info_ptrp = info_ptr;
     }
 
     return true;
@@ skipping 418 matching lines @@
     }
 
     if (1 == numberPasses) {
         return new SkPngScanlineDecoder(imageInfo, streamDeleter.detach(), chunkReader,
                                         png_ptr, info_ptr, bitDepth);
     }
 
     return new SkPngInterlacedScanlineDecoder(imageInfo, streamDeleter.detach(), chunkReader,
                                               png_ptr, info_ptr, bitDepth, numberPasses);
 }