Plumb OptDrawState down to VertexShaderBuilder

BUG=skia:

Review URL: https://codereview.chromium.org/628293002
diff --git a/tests/GLProgramsTest.cpp b/tests/GLProgramsTest.cpp
index a16173b..a0d6427 100644
--- a/tests/GLProgramsTest.cpp
+++ b/tests/GLProgramsTest.cpp
@@ -332,7 +332,9 @@
             return false;
         }
 
+        SkAutoTUnref<GrOptDrawState> optState(this->getDrawState().createOptState(*this->caps()));
         SkAutoTUnref<GrGLProgram> program(GrGLProgram::Create(this,
+                                                              *optState.get(),
                                                               pdesc,
                                                               geometryProcessor.get(),
                                                               stages,