Fixed regression in WEBGL_draw_buffers support

third_party/WebKit/Source/modules/webgl/WebGLDrawBuffers.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 122 matching lines @@
         gl->GenTextures(1, &depth);
         gl->BindTexture(GL_TEXTURE_2D, depth);
         gl->TexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, 1, 1, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, buffer);
     }
 
     Vector<Platform3DObject> colors;
     bool ok = true;
     GLint maxAllowedBuffers = std::min(maxDrawBuffers, maxColorAttachments);
     for (GLint i = 0; i < maxAllowedBuffers; ++i) {
         GLuint color;
+
         gl->GenTextures(1, &color);
         colors.append(color);
         gl->BindTexture(GL_TEXTURE_2D, color);
         gl->TexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
         gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + i, GL_TEXTURE_2D, color, 0);
         if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
             ok = false;
             break;
         }
         if (supportsDepth) {
             gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth, 0);
             if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
                 ok = false;
                 break;
             }
             gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
         }
         if (supportsDepthStencil) {
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthStencil, 0);
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, depthStencil, 0);
+            // For ES 2.0 contexts DEPTH_STENCIL is not available natively, so we emulate it
+            // at the command buffer level for WebGL contexts.
+            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D, depthStencil, 0);
             if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
                 ok = false;
                 break;
             }
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
+            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
         }
     }
 
     webglContext->restoreCurrentFramebuffer();
     gl->DeleteFramebuffers(1, &fbo);
     webglContext->restoreCurrentTexture2D();
     if (supportsDepth)
         gl->DeleteTextures(1, &depth);
     if (supportsDepthStencil)
         gl->DeleteTextures(1, &depthStencil);
     gl->DeleteTextures(colors.size(), colors.data());
+
     return ok;
 }
 
 } // namespace blink