Add support for debugger statement to top-level compiler.

src/fast-codegen.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 383 matching lines @@
   UNREACHABLE();
 }
 
 
 void FastCodeGenerator::VisitTryFinallyStatement(TryFinallyStatement* stmt) {
   UNREACHABLE();
 }
 
 
 void FastCodeGenerator::VisitDebuggerStatement(DebuggerStatement* stmt) {
-  UNREACHABLE();
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  Comment cmnt(masm_, "[ DebuggerStatement");
+  SetStatementPosition(stmt);
+  __ CallRuntime(Runtime::kDebugBreak, 0);
+  // Ignore the return value.
+#endif
 }
 
 
 void FastCodeGenerator::VisitFunctionBoilerplateLiteral(
     FunctionBoilerplateLiteral* expr) {
   UNREACHABLE();
 }
 
 
 void FastCodeGenerator::VisitConditional(Conditional* expr) {
@@ skipping 95 matching lines @@
 
 void FastCodeGenerator::VisitThisFunction(ThisFunction* expr) {
   UNREACHABLE();
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal