gpu: FBO must be incomplete if the attached texture is not cube complete.

gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc

Index: gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
diff --git a/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc b/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
index 2f052ac4e9fbf88d39afc691e3ffe2558e73f87b..37b4f0ed80d2417201dd798c131f731194491f6e 100644
--- a/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
+++ b/gpu/command_buffer/tests/gl_cube_map_texture_unittest.cc
@@ -125,14 +125,16 @@ TEST_P(GLCubeMapTextureTest, ReadPixelsFromIncompleteFBO) {
   // TODO(dshwang): remove the workaround when it's fixed. crbug.com/518889
   EXPECT_TRUE(glGetError() == GL_NO_ERROR);
 
+  // FBO is incomplete because the texture is not cube complete.
+  EXPECT_NE(static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE),
+            glCheckFramebufferStatus(GL_FRAMEBUFFER));
+
   GLsizei size = width_ * width_ * 4;
   scoped_ptr<uint8[]> pixels(new uint8[size]);
   // ANGLE crashes on glReadPixels() from incomplete FBO.
   glReadPixels(0, 0, width_, width_, GL_RGBA, GL_UNSIGNED_BYTE, pixels.get());
-  // According to spec, above glReadPixels() should fail and glGetError()
-  // should report an error, but some drivers are fine to bind incomplete cube
-  // map texture to FBO.
-  glGetError();
+  EXPECT_EQ(static_cast<GLenum>(GL_INVALID_FRAMEBUFFER_OPERATION),
+            glGetError());
 }
 
 }  // namespace gpu