Simplify various name flavors in VM.

runtime/vm/deopt_instructions.cc

Index: runtime/vm/deopt_instructions.cc
diff --git a/runtime/vm/deopt_instructions.cc b/runtime/vm/deopt_instructions.cc
index a926fdf7458427dd7a7c0510c4b130a6d45c249b..26ea335b7515f6fb0fb06a2b0e67d034a42232fb 100644
--- a/runtime/vm/deopt_instructions.cc
+++ b/runtime/vm/deopt_instructions.cc
@@ -143,18 +143,21 @@ DeoptContext::~DeoptContext() {
     TimelineStream* compiler_stream = isolate->GetCompilerStream();
     ASSERT(compiler_stream != NULL);
     if (compiler_stream->Enabled()) {
+      // Allocate what is needed before StarEvent, which is blocking allocation
+      // and GC until Complete.
       const Code& code = Code::Handle(zone(), code_);
       const Function& function = Function::Handle(zone(), code.function());
-      const char* function_name = function.QualifiedUserVisibleNameCString();
+      const String& function_name =
+          String::Handle(zone(), function.QualifiedUserVisibleName());
       const char* reason = DeoptReasonToCString(deopt_reason());
-      int counter = function.deoptimization_counter();
+      const int counter = function.deoptimization_counter();
       TimelineEvent* timeline_event = compiler_stream->StartEvent();
       if (timeline_event != NULL) {
         timeline_event->Duration("Deoptimize",
                                  deopt_start_micros_,
                                  OS::GetCurrentMonotonicMicros());
         timeline_event->SetNumArguments(3);
-        timeline_event->CopyArgument(0, "function", function_name);
+        timeline_event->CopyArgument(0, "function", function_name.ToCString());
         timeline_event->CopyArgument(1, "reason", reason);
         timeline_event->FormatArgument(2, "deoptimizationCount", "%d", counter);
         timeline_event->Complete();