Fix issue 3636, break on exception

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 "vm/code_generator.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 635 matching lines @@
     return true;
   }
   if (class_name.Equals("AssertionError")) {
     return true;
   }
   return false;
 }
 
 
 void Debugger::SignalExceptionThrown(const Object& exc) {
-  if (ignore_breakpoints_) {
+  if (ignore_breakpoints_ || (event_handler_ == NULL)) {
     return;
   }
   DebuggerStackTrace* stack_trace = CollectStackTrace();
   if (!ShouldPauseOnException(stack_trace, exc)) {
     return;
   }
   // No single-stepping possible after this pause event.
   last_bpt_line_ = -1;
-  if (event_handler_ != NULL) {
-    ASSERT(stack_trace_ == NULL);
-    stack_trace_ = stack_trace;
-    ASSERT(obj_cache_ == NULL);
-    obj_cache_ = new RemoteObjectCache(64);
-    DebuggerEvent event;
-    event.type = kExceptionThrown;
-    event.exception = &exc;
-    (*event_handler_)(&event);
-    stack_trace_ = NULL;
-    obj_cache_ = NULL;  // Remote object cache is zone allocated.
-  }
+  ASSERT(stack_trace_ == NULL);
+  stack_trace_ = stack_trace;
+  ASSERT(obj_cache_ == NULL);
+  obj_cache_ = new RemoteObjectCache(64);
+  DebuggerEvent event;
+  event.type = kExceptionThrown;
+  event.exception = &exc;
+  ASSERT(event_handler_ != NULL);
+  (*event_handler_)(&event);
+  stack_trace_ = NULL;
+  obj_cache_ = NULL;  // Remote object cache is zone allocated.
 }
 
 
 CodeBreakpoint* Debugger::MakeCodeBreakpoint(const Function& func,
                                              intptr_t token_index) {
   ASSERT(func.HasCode());
   ASSERT(!func.HasOptimizedCode());
   Code& code = Code::Handle(func.unoptimized_code());
   ASSERT(!code.IsNull());
   PcDescriptors& desc = PcDescriptors::Handle(code.pc_descriptors());
@@ skipping 648 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart