Add support to GrGLInterface for vertex array objects

src/gpu/gl/unix/GrGLCreateNativeInterface_unix.cpp

Index: src/gpu/gl/unix/GrGLCreateNativeInterface_unix.cpp
===================================================================
--- src/gpu/gl/unix/GrGLCreateNativeInterface_unix.cpp	(revision 7907)
+++ src/gpu/gl/unix/GrGLCreateNativeInterface_unix.cpp	(working copy)
@@ -164,6 +164,13 @@
         interface->fViewport = glViewport;
         GR_GL_GET_PROC(BindFragDataLocationIndexed);
 
+        if (glVer >= GR_GL_VER(3,0) || extensions.has("GL_ARB_vertex_array_object")) {
+            // no ARB suffix for GL_ARB_vertex_array_object
+            GR_GL_GET_PROC(BindVertexArray);
+            GR_GL_GET_PROC(GenVertexArrays);
+            GR_GL_GET_PROC(DeleteVertexArrays);
+        }
+
         // First look for GL3.0 FBO or GL_ARB_framebuffer_object (same since
         // GL_ARB_framebuffer_object doesn't use ARB suffix.)
         if (glVer >= GR_GL_VER(3,0) || extensions.has("GL_ARB_framebuffer_object")) {