Refactor separable varying location info to be stored in GrGLProgram subclass

src/gpu/gl/builders/GrGLProgramBuilder.h

Index: src/gpu/gl/builders/GrGLProgramBuilder.h
diff --git a/src/gpu/gl/builders/GrGLProgramBuilder.h b/src/gpu/gl/builders/GrGLProgramBuilder.h
index 5805cfc146661923e6c8ce2adfe566b6a18e48db..b564dbb46cd2401a0caaaa48fa0107b89e9647cd 100644
--- a/src/gpu/gl/builders/GrGLProgramBuilder.h
+++ b/src/gpu/gl/builders/GrGLProgramBuilder.h
@@ -12,6 +12,7 @@
 #include "GrGLGeometryShaderBuilder.h"
 #include "GrGLVertexShaderBuilder.h"
 #include "../GrGLProgramDataManager.h"
+#include "../GrGLPathProgramDataManager.h"
 #include "../GrGLUniformHandle.h"
 #include "../GrGLPrimitiveProcessor.h"
 #include "../GrGLXferProcessor.h"
@@ -39,6 +40,7 @@ public:
     virtual ~GrGLUniformBuilder() {}
 
     typedef GrGLProgramDataManager::UniformHandle UniformHandle;
+    typedef GrGLPathProgramDataManager::SeparableVaryingHandle SeparableVaryingHandle;
 
     /** Add a uniform variable to the current program, that has visibility in one or more shaders.
         visibility is a bitfield of ShaderVisibility values indicating from which shaders the
@@ -154,6 +156,12 @@ public:
     virtual void addPassThroughAttribute(const GrGeometryProcessor::Attribute*,
                                          const char* output) = 0;
 
+    /** Creates a fragment shader varying that can be referred to.
+     * Comparable to GrGLUniformBuilder::addUniform().
+     */
+    virtual SeparableVaryingHandle addSeparableVarying(
+        const char* name, GrGLVertToFrag*, GrSLPrecision fsPrecision = kDefault_GrSLPrecision) = 0;
+
     // TODO rename getFragmentBuilder
     virtual GrGLFragmentBuilder* getFragmentShaderBuilder() = 0;
     virtual GrGLVertexBuilder* getVertexShaderBuilder() = 0;
@@ -259,6 +267,10 @@ public:
     void addPassThroughAttribute(const GrPrimitiveProcessor::Attribute*,
                                  const char* output) override;
 
+    SeparableVaryingHandle addSeparableVarying(
+        const char* name,
+        GrGLVertToFrag*,
+        GrSLPrecision fsPrecision = kDefault_GrSLPrecision) override;
 
     // Handles for program uniforms (other than per-effect uniforms)
     struct BuiltinUniformHandles {
@@ -322,9 +334,9 @@ protected:
                       GrGLInstalledProc<Proc>*);
 
     GrGLProgram* finalize();
-    void bindUniformLocations(GrGLuint programID);
+    void bindProgramResourceLocations(GrGLuint programID);
     bool checkLinkStatus(GrGLuint programID);
-    void resolveUniformLocations(GrGLuint programID);
+    virtual void resolveProgramResourceLocations(GrGLuint programID);
     void cleanupProgram(GrGLuint programID, const SkTDArray<GrGLuint>& shaderIDs);
     void cleanupShaders(const SkTDArray<GrGLuint>& shaderIDs);