Remove SkBlitter::getShaderContext()

Unused.  Also ComposeShaderContext::getShaderContext{A,B}.

R=reed@google.com,mtklein@google.com

Change-Id: I36a8346f0c7e842455774339f388c04920db0040
Reviewed-on: https://skia-review.googlesource.com/7613
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>

src/core/SkBlitter.cpp

@@ -29,10 +29,6 @@ bool SkBlitter::resetShaderContext(const SkShader::ContextRec&) {
     return true;
 }
 
-SkShader::Context* SkBlitter::getShaderContext() const {
-    return nullptr;
-}
-
 const SkPixmap* SkBlitter::justAnOpaqueColor(uint32_t* value) {
     return nullptr;
 }

src/core/SkBlitter.h

@@ -111,7 +111,6 @@ public:
      *  Special methods for SkShaderBlitter. On all other classes this is a no-op.
      */
     virtual bool resetShaderContext(const SkShader::ContextRec&);
-    virtual SkShader::Context* getShaderContext() const;
 
     /**
      * Special methods for blitters that can blit more than one row at a time.

src/core/SkComposeShader.h

@@ -45,9 +45,6 @@ public:
         ComposeShaderContext(const SkComposeShader&, const ContextRec&,
                              SkShader::Context* contextA, SkShader::Context* contextB);
 
-        SkShader::Context* getShaderContextA() const { return fShaderContextA; }
-        SkShader::Context* getShaderContextB() const { return fShaderContextB; }
-
         virtual ~ComposeShaderContext();
 
         void shadeSpan(int x, int y, SkPMColor[], int count) override;

src/core/SkCoreBlitters.h

@@ -44,8 +44,6 @@ public:
       */
     bool resetShaderContext(const SkShader::ContextRec&) override;
 
-    SkShader::Context* getShaderContext() const override { return fShaderContext; }
-
 protected:
     uint32_t            fShaderFlags;
     const SkShader*     fShader;