Revert "Switch profiler from isolates to threads"

runtime/vm/debugger.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 2497 matching lines @@
 
 
 void Debugger::Pause(DebuggerEvent* event) {
   ASSERT(!IsPaused());  // No recursive pausing.
   ASSERT(obj_cache_ == NULL);
 
   pause_event_ = event;
   pause_event_->UpdateTimestamp();
   obj_cache_ = new RemoteObjectCache(64);
 
-  // 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());
-    InvokeEventHandler(event);
-  }
+  InvokeEventHandler(event);
 
   pause_event_ = NULL;
   obj_cache_ = NULL;    // Zone allocated
 }
 
 
 void Debugger::EnterSingleStepMode() {
   stepping_fp_ = 0;
   DeoptimizeWorld();
   isolate_->set_single_step(true);
@@ skipping 20 matching lines @@
     isolate_->set_single_step(true);
     // Find topmost caller that is debuggable.
     for (intptr_t i = 1; i < stack_trace->Length(); i++) {
       ActivationFrame* frame = stack_trace->FrameAt(i);
       if (frame->IsDebuggable()) {
         stepping_fp_ = frame->fp();
         break;
       }
     }
   }
+  if (!isolate_->single_step()) {
+    // We are no longer single stepping, make sure that the ThreadInterrupter
+    // is awake.
+    ThreadInterrupter::WakeUp();
+  }
 }
 
 
 // static
 bool Debugger::IsDebuggable(const Function& func) {
   if (!func.is_debuggable()) {
     return false;
   }
   if (ServiceIsolate::IsRunning()) {
     return true;
@@ skipping 676 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart