Disable direction pre-caching to suss out TSAN failures.

src/core/SkRecords.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkRecords_DEFINED
 #define SkRecords_DEFINED
 
@@ skipping 198 matching lines @@
     SkBitmap fBitmap;
 };
 
 // SkPath::getBounds() isn't thread safe unless we precache the bounds in a singlethreaded context.
 // SkPath::cheapComputeDirection() is similar.
 // Recording is a convenient time to cache these, or we can delay it to between record and playback.
 struct PreCachedPath : public SkPath {
     PreCachedPath() {}
     explicit PreCachedPath(const SkPath& path) : SkPath(path) {
         this->updateBoundsCache();
+#if 0  // Disabled to see if we ever really race on this.  It costs time, chromium:496982.
         SkPathPriv::FirstDirection junk;
         (void)SkPathPriv::CheapComputeFirstDirection(*this, &junk);
+#endif
     }
 };
 
 // Like SkPath::getBounds(), SkMatrix::getType() isn't thread safe unless we precache it.
 // This may not cover all SkMatrices used by the picture (e.g. some could be hiding in a shader).
 struct TypedMatrix : public SkMatrix {
     TypedMatrix() {}
     explicit TypedMatrix(const SkMatrix& matrix) : SkMatrix(matrix) {
         (void)this->getType();
     }
@@ skipping 128 matching lines @@
 #undef RECORD0
 #undef RECORD1
 #undef RECORD2
 #undef RECORD3
 #undef RECORD4
 #undef RECORD5
 
 }  // namespace SkRecords
 
 #endif//SkRecords_DEFINED