fix comma in GrAuditTrail json

include/private/GrAuditTrail.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrAuditTrail_DEFINED
 #define GrAuditTrail_DEFINED
 
@@ skipping 74 matching lines @@
     struct Frame : public Event {
         SkString toJson() const override;
         FrameArray fChildren;
     };
 
     struct Batch : public Event {
         SkString toJson() const override;
         SkRect fBounds;
     };
 
-    static void JsonifyTArray(SkString* json, const char* name, const FrameArray& array);
+    static void JsonifyTArray(SkString* json, const char* name, const FrameArray& array,
+                              bool addComma);
 
     FrameArray fFrames;
     SkTArray<Frame*> fStack;
     uint64_t fUniqueID;
 };
 
 #define GR_AUDIT_TRAIL_INVOKE_GUARD(invoke, ...) \
     if (GR_BATCH_DEBUGGING_OUTPUT) {             \
         invoke(__VA_ARGS__);                     \
     }
 
 #define GR_AUDIT_TRAIL_AUTO_FRAME(audit_trail, framename) \
     GrAuditTrail::AutoFrame SK_MACRO_APPEND_LINE(auto_frame)(audit_trail, framename);
 
 #define GR_AUDIT_TRAIL_RESET(audit_trail) \
     GR_AUDIT_TRAIL_INVOKE_GUARD(audit_trail->reset);
 
 #define GR_AUDIT_TRAIL_ADDBATCH(audit_trail, batchname, bounds) \
     GR_AUDIT_TRAIL_INVOKE_GUARD(audit_trail->addBatch, batchname, bounds);
 
 #endif