Unify implementations of stroking radius calculations

src/gpu/batches/GrTessellatingPathRenderer.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrTessellatingPathRenderer.h"
 
 #include "GrBatchFlushState.h"
@@ skipping 240 matching lines @@
         const SkRect& pathBounds = path.getBounds();
         fClipBounds = clipBounds;
         // Because the clip bounds are used to add a contour for inverse fills, they must also
         // include the path bounds.
         fClipBounds.join(pathBounds);
         if (path.isInverseFillType()) {
             fBounds = fClipBounds;
         } else {
             fBounds = path.getBounds();
         }
-        if (!stroke.isFillStyle()) {
-            SkScalar radius = SkScalarHalf(stroke.getWidth());
-            if (stroke.getJoin() == SkPaint::kMiter_Join) {
-                SkScalar scale = stroke.getMiter();
-                if (scale > SK_Scalar1) {
-                    radius = SkScalarMul(radius, scale);
-                }
-            }
-            fBounds.outset(radius, radius);
-        }
+        SkScalar radius = stroke.getInflationRadius();
+        fBounds.outset(radius, radius);
         viewMatrix.mapRect(&fBounds);
     }
 
     GrColor                 fColor;
     SkPath                  fPath;
     GrStrokeInfo            fStroke;
     SkMatrix                fViewMatrix;
     SkRect                  fClipBounds; // in source space
     GrXPOverridesForBatch   fPipelineInfo;
 
@@ skipping 38 matching lines @@
     bool result = viewMatrix.invert(&vmi);
     if (!result) {
         SkFAIL("Cannot invert matrix\n");
     }
     vmi.mapRect(&clipBounds);
     GrStrokeInfo strokeInfo = GrTest::TestStrokeInfo(random);
     return TessellatingPathBatch::Create(color, path, strokeInfo, viewMatrix, clipBounds);
 }
 
 #endif