Timeline service protocol support with Observatory UI

runtime/vm/debugger.cc

Index: runtime/vm/debugger.cc
diff --git a/runtime/vm/debugger.cc b/runtime/vm/debugger.cc
index 2c4d54bf04c0bd6dbd76796dab0c00c1fefdd77a..92a8ec544422ea9e372c467301d6fb90372b8047 100644
--- a/runtime/vm/debugger.cc
+++ b/runtime/vm/debugger.cc
@@ -2518,7 +2518,11 @@ void Debugger::Pause(DebuggerEvent* event) {
   // We are about to invoke the debuggers event handler. Disable interrupts
   // for this thread while waiting for debug commands over the service protocol.
   {
-    DisableThreadInterruptsScope dtis(Thread::Current());
+    Thread* thread = Thread::Current();
+    DisableThreadInterruptsScope dtis(thread);
+    TimelineDurationScope tds(thread,
+                              isolate_->GetDebuggerStream(),
+                              "Debugger Pause");
     InvokeEventHandler(event);
   }