Forward declare SkStrokeRec in SkPathEffect

tests/DashPathEffectTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Test.h"
 
 #include "SkDashPathEffect.h"
 #include "SkWriteBuffer.h"
+#include "SkStrokeRec.h"
 
 // crbug.com/348821 was rooted in SkDashPathEffect refusing to flatten and unflatten itself when
 // fInitialDashLength < 0 (a signal the effect is nonsense).  Here we test that it flattens.
 
 DEF_TEST(DashPathEffectTest_crbug_348821, r) {
     SkScalar intervals[] = { 1.76934361e+36f, 2.80259693e-45f };  // Values from bug.
     const int count = 2;
     SkScalar phase = SK_ScalarInfinity;  // Used to force the bad fInitialDashLength = -1 path.
     SkAutoTUnref<SkDashPathEffect> dash(SkDashPathEffect::Create(intervals, count, phase));
 
@@ skipping 57 matching lines @@
                 if (i < 2) {
                     REPORTER_ASSERT(r, actualResult == testCases[j].fExpectedResult);
                 } else {
                     // On the third pass all the lines should be outside the translated cull rect
                     REPORTER_ASSERT(r, !actualResult);
                 }
             }
         }
     }
 }