unify peekPixels around pixmap parameter

src/gpu/SkGr.cpp

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkGr.h"
 #include "SkGrPriv.h"
@@ skipping 245 matching lines @@
         } else {
             SkImageInfo info = SkImageInfo::MakeN32Premul(pixmap.width(), pixmap.height());
             tmpBitmap.allocPixels(info);
             if (!pixmap.readPixels(info, tmpBitmap.getPixels(), tmpBitmap.rowBytes())) {
                 return nullptr;
             }
             if (!tmpBitmap.peekPixels(&tmpPixmap)) {
                 return nullptr;
             }
             pmap = &tmpPixmap;
+            // must rebuild desc, since we've forced the info to be N32
+            desc = GrImageInfoToSurfaceDesc(pmap->info());
         }
     }
 
     return ctx->textureProvider()->createTexture(desc, SkBudgeted::kYes, pmap->addr(),
                                                  pmap->rowBytes());
 }
 
 
 ////////////////////////////////////////////////////////////////////////////////
 
@@ skipping 418 matching lines @@
             SkErrorInternals::SetError( kInvalidPaint_SkError,
                                         "Sorry, I don't understand the filtering "
                                         "mode you asked for.  Falling back to "
                                         "MIPMaps.");
             textureFilterMode = GrTextureParams::kMipMap_FilterMode;
             break;
 
     }
     return textureFilterMode;
 }