Emit symbol maps for compiled code for use by the Linux perf tool.

runtime/include/dart_api.h

Index: runtime/include/dart_api.h
diff --git a/runtime/include/dart_api.h b/runtime/include/dart_api.h
index 86f9b2a033d2bec7f81757a597bb2e664b0dc5fa..500e744346d3c55b2a834de9a1c56a3d2dbeeb5f 100755
--- a/runtime/include/dart_api.h
+++ b/runtime/include/dart_api.h
@@ -2583,8 +2583,12 @@ DART_EXPORT Dart_Handle Dart_SetNativeResolver(
 DART_EXPORT void Dart_InitPprofSupport();
 DART_EXPORT void Dart_GetPprofSymbolInfo(void** buffer, int* buffer_size);
 
+typedef void (*Dart_FileWriterFunction)(const char* buffer, int64_t num_bytes);
+
+// Support for generating symbol maps for use by the Linux perf tool.
+DART_EXPORT void Dart_InitPerfEventsSupport(Dart_FileWriterFunction function);
+
 // Support for generating flow graph compiler debugging output into a file.
-typedef void (*FileWriterFunction)(const char* buffer, int64_t num_bytes);
-DART_EXPORT void Dart_InitFlowGraphPrinting(FileWriterFunction function);
+DART_EXPORT void Dart_InitFlowGraphPrinting(Dart_FileWriterFunction function);
 
 #endif  // INCLUDE_DART_API_H_