Fix the bug for VertexAttrib{I}Pointer when no array buffer bound

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 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 "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
@@ skipping 10891 matching lines @@
   GLuint indx = c.indx;
   GLint size = c.size;
   GLenum type = c.type;
   GLsizei stride = c.stride;
   GLsizei offset = c.offset;
 
   if (!state_.bound_array_buffer.get() ||
       state_.bound_array_buffer->IsDeleted()) {
     if (state_.vertex_attrib_manager.get() ==
         state_.default_vertex_attrib_manager.get()) {
-      LOCAL_SET_GL_ERROR(
-          GL_INVALID_OPERATION,
-          "glVertexAttribIPointer", "no array buffer bound");
-      return error::kNoError;
+      if (offset != 0) {

[Zhenyao Mo, 2017/01/09 18:21:15]

I think you can combine this and the else to a simple (offset != 0) condition,
and the error message can just be "offset != 0".

[yunchao, 2017/01/10 14:10:11]

Done.

+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_OPERATION,
+            "glVertexAttribIPointer",
+            "no array buffer is bound and offset is non-zero");
+        return error::kNoError;
+      }
     } else if (offset != 0) {
       LOCAL_SET_GL_ERROR(
           GL_INVALID_OPERATION,
           "glVertexAttribIPointer", "client side arrays are not allowed");
       return error::kNoError;
     }
   }
 
   const void* ptr = reinterpret_cast<const void*>(offset);
   if (!validators_->vertex_attrib_i_type.IsValid(type)) {
@@ skipping 69 matching lines @@
   GLint size = c.size;
   GLenum type = c.type;
   GLboolean normalized = static_cast<GLboolean>(c.normalized);
   GLsizei stride = c.stride;
   GLsizei offset = c.offset;
 
   if (!state_.bound_array_buffer.get() ||
       state_.bound_array_buffer->IsDeleted()) {
     if (state_.vertex_attrib_manager.get() ==
         state_.default_vertex_attrib_manager.get()) {
-      LOCAL_SET_GL_ERROR(
-          GL_INVALID_OPERATION,
-          "glVertexAttribPointer", "no array buffer bound");
-      return error::kNoError;
+      if (offset != 0) {

[Zhenyao Mo, 2017/01/09 18:21:15]

Same here.

[yunchao, 2017/01/10 14:10:11]

Done.

+        LOCAL_SET_GL_ERROR(
+            GL_INVALID_OPERATION,
+            "glVertexAttribPointer",
+            "no array buffer is bound and offset is non-zero");
+        return error::kNoError;
+      }
     } else if (offset != 0) {
       LOCAL_SET_GL_ERROR(
           GL_INVALID_OPERATION,
           "glVertexAttribPointer", "client side arrays are not allowed");
       return error::kNoError;
     }
   }
   const void* ptr = reinterpret_cast<const void*>(offset);
   if (!validators_->vertex_attrib_type.IsValid(type)) {
     LOCAL_SET_GL_ERROR_INVALID_ENUM("glVertexAttribPointer", type, "type");
@@ skipping 8099 matching lines @@
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "base/macros.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu