Add ShaderBuilders to EmitArgs and remove gettings from ProgBuilder.

gm/dcshader.cpp

Index: gm/dcshader.cpp
diff --git a/gm/dcshader.cpp b/gm/dcshader.cpp
index d22ab023df85890bda916bd09b485fd31519d155..4dedf74093e0bb8c04af2dd2c45457b8b7ce1f8e 100644
--- a/gm/dcshader.cpp
+++ b/gm/dcshader.cpp
@@ -67,16 +67,17 @@ public:
     GrGLSLFragmentProcessor* onCreateGLSLInstance() const override {
         class DCGLFP : public GrGLSLFragmentProcessor {
             void emitCode(EmitArgs& args) override {
-                GrGLSLFragmentBuilder* fpb = args.fBuilder->getFragmentShaderBuilder();
-                fpb->codeAppendf("vec2 c = %s;", fpb->ensureFSCoords2D(args.fCoords, 0).c_str());
-                fpb->codeAppend("vec2 r = mod(c, vec2(20.0));");
-                fpb->codeAppend("vec4 color = vec4(0.5*sin(c.x / 15.0) + 0.5,"
-                                                    "0.5*cos((c.x + c.y) / 15.0) + 0.5,"
-                                                    "(r.x + r.y) / 20.0,"
-                                                    "distance(r, vec2(15.0)) / 20.0 + 0.2);");
-                fpb->codeAppendf("color.rgb *= color.a;"
-                                    "%s = color * %s;",
-                                    args.fOutputColor, GrGLSLExpr4(args.fInputColor).c_str());
+                GrGLSLFragmentBuilder* fragBuilder = args.fFragBuilder;
+                fragBuilder->codeAppendf("vec2 c = %s;",
+                                         fragBuilder->ensureFSCoords2D(args.fCoords, 0).c_str());
+                fragBuilder->codeAppend("vec2 r = mod(c, vec2(20.0));");
+                fragBuilder->codeAppend("vec4 color = vec4(0.5*sin(c.x / 15.0) + 0.5,"
+                                                      "0.5*cos((c.x + c.y) / 15.0) + 0.5,"
+                                                      "(r.x + r.y) / 20.0,"
+                                                      "distance(r, vec2(15.0)) / 20.0 + 0.2);");
+                fragBuilder->codeAppendf("color.rgb *= color.a;"
+                                         "%s = color * %s;",
+                                         args.fOutputColor, GrGLSLExpr4(args.fInputColor).c_str());
             }
             void onSetData(const GrGLSLProgramDataManager&, const GrProcessor&) override {}
         };