Simplify adding attributes to GrGeometryProcessor

src/gpu/GrGeometryProcessor.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGeometryProcessor_DEFINED
 #define GrGeometryProcessor_DEFINED
 
@@ skipping 35 matching lines @@
 protected:
     /**
      * Subclasses call this from their constructor to register vertex attributes.  Attributes
      * will be padded to the nearest 4 bytes for performance reasons.
      * TODO After deferred geometry, we should do all of this inline in GenerateGeometry alongside
      * the struct used to actually populate the attributes.  This is all extremely fragile, vertex
      * attributes have to be added in the order they will appear in the struct which maps memory.
      * The processor key should reflect the vertex attributes, or there lack thereof in the
      * GrGeometryProcessor.
      */
-    const Attribute& addVertexAttrib(const Attribute& attribute) {
-        fVertexStride += attribute.fOffset;
-        fAttribs.push_back(attribute);
+    const Attribute& addVertexAttrib(const char* name, GrVertexAttribType type,
+                                     GrSLPrecision precision = kDefault_GrSLPrecision) {
+        fAttribs.emplace_back(name, type, precision);
+        fVertexStride += fAttribs.back().fOffset;
         return fAttribs.back();
     }
 
     void setWillUseGeoShader() { fWillUseGeoShader = true; }
 
     /**
      * If a GrFragmentProcessor in the GrPipeline needs localCoods, we will provide them in one of
      * three ways
      * 1) LocalCoordTransform * Position - in Shader
      * 2) LocalCoordTransform * ExplicitLocalCoords- in Shader
@@ skipping 21 matching lines @@
 
 private:
     bool fWillUseGeoShader;
     LocalCoordsType fLocalCoordsType;
     float fSampleShading;
 
     typedef GrPrimitiveProcessor INHERITED;
 };
 
 #endif