Move shader precision modifier check onto GLSLCaps

src/gpu/gl/GrGLGLSL.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrGLGLSL.h"
+#include "GrGLContext.h"
 #include "GrGLShaderVar.h"
+#include "GrGLUtil.h"
 #include "SkString.h"
 
 bool GrGLGetGLSLGeneration(const GrGLInterface* gl, GrGLSLGeneration* generation) {
     SkASSERT(generation);
     GrGLSLVersion ver = GrGLGetGLSLVersion(gl);
     if (GR_GLSL_INVALID_VER == ver) {
         return false;
     }
     switch (gl->fStandard) {
         case kGL_GrGLStandard:
@@ skipping 80 matching lines @@
                 out->append("precision mediump float;\n");
                 break;
             case kLow_GrSLPrecision:
                 out->append("precision lowp float;\n");
                 break;
             default:
                 SkFAIL("Unknown precision value.");
         }
     }
 }