Make GrShape compute keys for short paths from path data instead of using the gen id.

src/core/SkPathPriv.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPathPriv_DEFINED
 #define SkPathPriv_DEFINED
 
@@ skipping 80 matching lines @@
      */
     static bool IsSimpleClosedRect(const SkPath& path, SkRect* rect, SkPath::Direction* direction,
                                    unsigned* start);
 
     /**
      * Creates a path from arc params using the semantics of SkCanvas::drawArc. This function
      * assumes empty ovals and zero sweeps have already been filtered out.
      */
     static void CreateDrawArcPath(SkPath* path, const SkRect& oval, SkScalar startAngle,
                                   SkScalar sweepAngle, bool useCenter, bool isFillNoPathEffect);
+
+    /**
+     * Returns a pointer to the verb data. Note that the verbs are stored backwards in memory and
+     * thus the returned pointer is the last verb.
+     */
+    static const uint8_t* VerbData(const SkPath& path) {
+        return path.fPathRef->verbsMemBegin();
+    }
+
+    /** Returns a raw pointer to the path points */
+    static const SkPoint* PointData(const SkPath& path) {
+        return path.fPathRef->points();
+    }
+
+    /** Returns the number of conic weights in the path */
+    static int ConicWeightCnt(const SkPath& path) {
+        return path.fPathRef->countWeights();
+    }
+
+    /** Returns a raw pointer to the path conic weights. */
+    static const SkScalar* ConicWeightData(const SkPath& path) {
+        return path.fPathRef->conicWeights();
+    }
 };
 
 #endif