Revert of Change desktop and ES 3.0 to always use sized internal texture formats.

src/gpu/gl/GrGpuGL.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGpuGL.h"
 #include "GrGLStencilBuffer.h"
@@ skipping 540 matching lines @@
         // 565 we always use an unsized internal format to let the system pick
         // the best sized format to convert the 565 data to. Since TexStorage
         // only allows sized internal formats we will instead use TexImage2D.
         useTexStorage = desc.fConfig != kRGB_565_GrPixelConfig;
     }
 
     GrGLenum internalFormat;
     GrGLenum externalFormat = 0x0; // suprress warning
     GrGLenum externalType = 0x0;// suprress warning
 
-    // glTexStorage requires sized internal formats on both desktop and ES.
-    // ES2 requires an unsized format for glTexImage. On ES3 and desktop we default to sized.
-    bool useSizedFormat = useTexStorage || kGL_GrGLStandard == this->glStandard() ||
-                          this->glVersion() >= GR_GL_VER(3, 0);
+    // glTexStorage requires sized internal formats on both desktop and ES. ES2 requires an unsized
+    // format for glTexImage, unlike ES3 and desktop. However, we allow the driver to decide the
+    // size of the internal format whenever possible and so only use a sized internal format when
+    // using texture storage.
+    bool useSizedFormat = useTexStorage;
+    // Many versions of the ES3 drivers on various platforms will not accept GL_RED in
+    // glTexImage2D for the internal format but will accept GL_R8.
+    if (kGLES_GrGLStandard == this->glStandard() && this->glVersion() >= GR_GL_VER(3, 0) &&
+        kAlpha_8_GrPixelConfig == dataConfig) {
+        useSizedFormat = true;
+    }
     if (!this->configToGLFormats(dataConfig, useSizedFormat, &internalFormat,
                                  &externalFormat, &externalType)) {
         return false;
     }
 
     /*
      *  check whether to allocate a temporary buffer for flipping y or
      *  because our srcData has extra bytes past each row. If so, we need
      *  to trim those off here, since GL ES may not let us specify
      *  GL_UNPACK_ROW_LENGTH.
@@ skipping 2007 matching lines @@
             this->setVertexArrayID(gpu, 0);
         }
         int attrCount = gpu->glCaps().maxVertexAttributes();
         if (fDefaultVertexArrayAttribState.count() != attrCount) {
             fDefaultVertexArrayAttribState.resize(attrCount);
         }
         attribState = &fDefaultVertexArrayAttribState;
     }
     return attribState;
 }