Emit Timeline events for most Dart_API calls

runtime/vm/dart_api_impl.h

Index: runtime/vm/dart_api_impl.h
diff --git a/runtime/vm/dart_api_impl.h b/runtime/vm/dart_api_impl.h
index ccd8fa1f3a5fbdbdf53ec38adf08b494aba4ba7f..6172e1a9433fbc74a0133ff214db0698fdcf2fdc 100644
--- a/runtime/vm/dart_api_impl.h
+++ b/runtime/vm/dart_api_impl.h
@@ -11,8 +11,6 @@
 
 namespace dart {
 
-DECLARE_FLAG(bool, trace_api);
-
 class ApiLocalScope;
 class ApiState;
 class FinalizablePersistentHandle;
@@ -24,20 +22,9 @@ const char* CanonicalFunction(const char* func);
 
 #define CURRENT_FUNC CanonicalFunction(__FUNCTION__)
 
-#if defined(DEBUG)
-#define TRACE_API_CALL(name)                                                   \
-  if (FLAG_trace_api) {                                                        \
-    OS::Print("Calling API func: %s\n", name);                                 \
-  }
-#else
-#define TRACE_API_CALL(name)
-#endif
-
-
 // Checks that the current isolate is not NULL.
 #define CHECK_ISOLATE(isolate)                                                 \
   do {                                                                         \
-    TRACE_API_CALL(CURRENT_FUNC);                                              \
     if ((isolate) == NULL) {                                                   \
       FATAL1("%s expects there to be a current isolate. Did you "              \
              "forget to call Dart_CreateIsolate or Dart_EnterIsolate?",        \
@@ -48,7 +35,6 @@ const char* CanonicalFunction(const char* func);
 // Checks that the current isolate is NULL.
 #define CHECK_NO_ISOLATE(isolate)                                              \
   do {                                                                         \
-    TRACE_API_CALL(CURRENT_FUNC);                                              \
     if ((isolate) != NULL) {                                                   \
       FATAL1("%s expects there to be no current isolate. Did you "             \
              "forget to call Dart_ExitIsolate?", CURRENT_FUNC);                \