Disable the profiler when a debugger is attached

runtime/vm/thread_interrupter_linux.cc

Index: runtime/vm/thread_interrupter_linux.cc
diff --git a/runtime/vm/thread_interrupter_linux.cc b/runtime/vm/thread_interrupter_linux.cc
index 167581edf0cec81fe2e68dbb94aadf9afb5448d8..6c4fdb2a133239e3f8a9a7a21d41e6f49a7cc63e 100644
--- a/runtime/vm/thread_interrupter_linux.cc
+++ b/runtime/vm/thread_interrupter_linux.cc
@@ -44,10 +44,15 @@ class ThreadInterrupterLinux : public AllStatic {
 };
 
 
+bool ThreadInterrupter::IsDebuggerAttached() {
+  return false;
+}
+
+
 void ThreadInterrupter::InterruptThread(OSThread* thread) {
   if (FLAG_trace_thread_interrupter) {
-    OS::Print("ThreadInterrupter interrupting %p\n",
-              reinterpret_cast<void*>(thread->id()));
+    OS::PrintErr("ThreadInterrupter interrupting %p\n",
+                 reinterpret_cast<void*>(thread->id()));
   }
   int result = pthread_kill(thread->id(), SIGPROF);
   ASSERT((result == 0) || (result == ESRCH));