Always support pack/unpack row length on ES3. Add support for NV_pack_subimage extension.

src/gpu/gl/GrGLCaps.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLCaps.h"
 #include "GrGLContext.h"
@@ skipping 129 matching lines @@
     } else {
         fTextureSwizzleSupport = false;
     }
 
     if (kDesktop_GrGLBinding == binding) {
         fUnpackRowLengthSupport = true;
         fUnpackFlipYSupport = false;
         fPackRowLengthSupport = true;
         fPackFlipYSupport = false;
     } else {
-        fUnpackRowLengthSupport =ctxInfo.hasExtension("GL_EXT_unpack_subimage");
+        fUnpackRowLengthSupport = version >= GR_GL_VER(3,0) ||
+                                  ctxInfo.hasExtension("GL_EXT_unpack_subimage");
         fUnpackFlipYSupport = ctxInfo.hasExtension("GL_CHROMIUM_flipy");
-        // no extension for pack row length
-        fPackRowLengthSupport = false;
+        fPackRowLengthSupport = version >= GR_GL_VER(3,0) ||
+                                ctxInfo.hasExtension("GL_NV_pack_subimage");
         fPackFlipYSupport =
             ctxInfo.hasExtension("GL_ANGLE_pack_reverse_row_order");
     }
 
     fTextureUsageSupport = (kES_GrGLBinding == binding) &&
                             ctxInfo.hasExtension("GL_ANGLE_texture_usage");
 
     // Tex storage is in desktop 4.2 and can be an extension to desktop or ES.
     fTexStorageSupport = (kDesktop_GrGLBinding == binding &&
                           version >= GR_GL_VER(4,2)) ||
@@ skipping 426 matching lines @@
     GrPrintf("GL_ARB_imaging support: %s\n", (fImagingSupport ? "YES": "NO"));
     GrPrintf("Two Format Limit: %s\n", (fTwoFormatLimit ? "YES": "NO"));
     GrPrintf("Fragment coord conventions support: %s\n",
              (fFragCoordsConventionSupport ? "YES": "NO"));
     GrPrintf("Vertex array object support: %s\n", (fVertexArrayObjectSupport ? "YES": "NO"));
     GrPrintf("Use non-VBO for dynamic data: %s\n",
              (fUseNonVBOVertexAndIndexDynamicData ? "YES" : "NO"));
     GrPrintf("Core Profile: %s\n", (fIsCoreProfile ? "YES" : "NO"));
     GrPrintf("Discard FrameBuffer support: %s\n", (fDiscardFBSupport ? "YES" : "NO"));
 }