Fix app gl state restore

android_webview/browser/in_process_renderer/in_process_view_renderer.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/browser/in_process_renderer/in_process_view_renderer.h"
 
 #include <android/bitmap.h>
 
 #include "android_webview/public/browser/draw_gl.h"
 #include "android_webview/public/browser/draw_sw.h"
@@ skipping 33 matching lines @@
 
 namespace android_webview {
 
 namespace {
 
 class GLStateRestore {
  public:
   GLStateRestore() {
     glGetIntegerv(GL_TEXTURE_BINDING_EXTERNAL_OES,
                   &texture_external_oes_binding_);
-    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &vertex_array_buffer_binding_);
-    glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING,
-                  &index_array_buffer_binding_);

[joth, 2013/05/28 20:44:05]

can we leave this in under !NDEBUG just to keep the DCHECK? We should track down
and fix whatever is causing this to read non-zero values

     glGetIntegerv(GL_PACK_ALIGNMENT, &pack_alignment_);
     glGetIntegerv(GL_UNPACK_ALIGNMENT, &unpack_alignment_);
 
     for (size_t i = 0; i < ARRAYSIZE_UNSAFE(vertex_attrib_); ++i) {
       glGetVertexAttribiv(
           i, GL_VERTEX_ATTRIB_ARRAY_ENABLED, &vertex_attrib_[i].enabled);
       glGetVertexAttribiv(
           i, GL_VERTEX_ATTRIB_ARRAY_SIZE, &vertex_attrib_[i].size);
       glGetVertexAttribiv(
           i, GL_VERTEX_ATTRIB_ARRAY_TYPE, &vertex_attrib_[i].type);
@@ skipping 11 matching lines @@
     glGetBooleanv(GL_BLEND, &blend_enabled_);
     glGetIntegerv(GL_BLEND_SRC_RGB, &blend_src_rgb_);
     glGetIntegerv(GL_BLEND_SRC_ALPHA, &blend_src_alpha_);
     glGetIntegerv(GL_BLEND_DST_RGB, &blend_dest_rgb_);
     glGetIntegerv(GL_BLEND_DST_ALPHA, &blend_dest_alpha_);
     glGetIntegerv(GL_ACTIVE_TEXTURE, &active_texture_);
     glGetIntegerv(GL_VIEWPORT, viewport_);
     glGetBooleanv(GL_SCISSOR_TEST, &scissor_test_);
     glGetIntegerv(GL_SCISSOR_BOX, scissor_box_);
     glGetIntegerv(GL_CURRENT_PROGRAM, &current_program_);
-
-    DCHECK_EQ(0, vertex_array_buffer_binding_);
-    DCHECK_EQ(0, index_array_buffer_binding_);
   }
 
   ~GLStateRestore() {
     glBindTexture(GL_TEXTURE_EXTERNAL_OES, texture_external_oes_binding_);
-    glBindBuffer(GL_ARRAY_BUFFER, vertex_array_buffer_binding_);
-    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_array_buffer_binding_);
     glPixelStorei(GL_PACK_ALIGNMENT, pack_alignment_);
     glPixelStorei(GL_UNPACK_ALIGNMENT, unpack_alignment_);
 
     for (size_t i = 0; i < ARRAYSIZE_UNSAFE(vertex_attrib_); ++i) {
       glVertexAttribPointer(i,
                             vertex_attrib_[i].size,
                             vertex_attrib_[i].type,
                             vertex_attrib_[i].normalized,
                             vertex_attrib_[i].stride,
                             vertex_attrib_[i].pointer);
@@ skipping 34 matching lines @@
     if (scissor_test_) {
       glEnable(GL_SCISSOR_TEST);
     } else {
       glDisable(GL_SCISSOR_TEST);
     }
 
     glScissor(
         scissor_box_[0], scissor_box_[1], scissor_box_[2], scissor_box_[3]);
 
     glUseProgram(current_program_);
+
+    glBindBuffer(GL_ARRAY_BUFFER, 0);

[no sievers, 2013/05/28 20:04:04]

Interesting, so it's expected that draw functor invocation resets this to zero
instead of what it previously was? Maybe put a comment that the framework
somehow expects this?

[joth, 2013/05/28 20:44:05]

Today, Framework ensures nothing is bound when we're invoked, and expects the
same when we return. Bo thinks the problem is something else in our code is
binding this state outside of the functor call (i.e. we're tripping up over our
own bug). 
Hence my suggestion to keep the debug only DCHECK in the c'tor.

+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
   }
 
  private:
   GLint texture_external_oes_binding_;
-  GLint vertex_array_buffer_binding_;
-  GLint index_array_buffer_binding_;
   GLint pack_alignment_;
   GLint unpack_alignment_;
 
   struct {
     GLint enabled;
     GLint size;
     GLint type;
     GLint normalized;
     GLint stride;
     GLvoid* pointer;
@@ skipping 413 matching lines @@
   // TODO(joth): BrowserViewRendererImpl had a bunch of logic for dpi and page
   // scale here. Determine what if any needs bringing over to this class.
   return CompositeSW(canvas);
 }
 
 bool InProcessViewRenderer::CompositeSW(SkCanvas* canvas) {
   return compositor_ && compositor_->DemandDrawSw(canvas);
 }
 
 }  // namespace android_webview