Split default and user-supplied event tracers.

include/utils/SkEventTracer.h

 /*
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkEventTracer_DEFINED
 #define SkEventTracer_DEFINED
 
@@ skipping 11 matching lines @@
 // to explicitly enable the event.
 #define TRACE_DISABLED_BY_DEFAULT(name) "disabled-by-default-" name
 
 class SK_API SkEventTracer {
 public:
 
     typedef uint64_t Handle;
 
     static SkEventTracer* GetInstance();
 
-    static void SetInstance(SkEventTracer* tracer) {
-        SkDELETE(SkEventTracer::gInstance);
-        SkEventTracer::gInstance = tracer;
-    }
+    static void SetInstance(SkEventTracer*);
 
     virtual ~SkEventTracer() { }
 
     // The pointer returned from GetCategoryGroupEnabled() points to a
     // value with zero or more of the following bits. Used in this class only.
     // The TRACE_EVENT macros should only use the value as a bool.
     // These values must be in sync with macro values in trace_event.h in chromium.
     enum CategoryGroupEnabledFlags {
         // Category group enabled for the recording mode.
         kEnabledForRecording_CategoryGroupEnabledFlags = 1 << 0,
@@ skipping 15 matching lines @@
                       int32_t numArgs,
                       const char** argNames,
                       const uint8_t* argTypes,
                       const uint64_t* argValues,
                       uint8_t flags) = 0;
 
     virtual void
         updateTraceEventDuration(const uint8_t* categoryEnabledFlag,
                                  const char* name,
                                  SkEventTracer::Handle handle) = 0;
-private:
-    static SkEventTracer *gInstance;
 };
 
 #endif // SkEventTracer_DEFINED