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

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

Index: third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
diff --git a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
index 548737c8af2f6d93b4b25d97ade7737c882df962..56c3ab8b0313c426fc6d9ea0da25a3c5c8811294 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
+++ b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
@@ -6126,9 +6126,9 @@ void WebGLRenderingContextBase::vertexAttribPointer(GLuint index,
   }
   if (!validateValueFitNonNegInt32("vertexAttribPointer", "offset", offset))
     return;
-  if (!m_boundArrayBuffer) {
+  if (!m_boundArrayBuffer && offset != 0) {
     synthesizeGLError(GL_INVALID_OPERATION, "vertexAttribPointer",
-                      "no bound ARRAY_BUFFER");
+                      "no ARRAY_BUFFER is bound and offset is non-zero");
     return;
   }