Ignore pause on debugger statement when breakpoints are disabled

This behavior was changed in https://codereview.chromium.org/1402913002.
It's pretty usefull to have ability to disable debugger statement for our users.

BUG=chromium:583515
LOG=N
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/1690173002

Cr-Commit-Position: refs/heads/master@{#33960}

src/debug/debug.h

@@ -525,6 +525,7 @@ class Debug {
     return !!base::NoBarrier_Load(&thread_local_.current_debug_scope_);
   }
   void set_break_points_active(bool v) { break_points_active_ = v; }
+  bool break_points_active() const { return break_points_active_; }
 
   StackFrame::Id break_frame_id() { return thread_local_.break_frame_id_; }
   int break_id() { return thread_local_.break_id_; }

src/runtime/runtime-debug.cc

@@ -30,7 +30,9 @@ RUNTIME_FUNCTION(Runtime_DebugBreak) {
 RUNTIME_FUNCTION(Runtime_HandleDebuggerStatement) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 0);
+  if (isolate->debug()->break_points_active()) {
     isolate->debug()->HandleDebugBreak();
+  }
   return isolate->heap()->undefined_value();
 }
 

test/cctest/test-debug.cc

@@ -4327,6 +4327,22 @@ TEST(DisableBreak) {
   CheckDebuggerUnloaded(env->GetIsolate());
 }
 
+TEST(DisableDebuggerStatement) {
+  DebugLocalContext env;
+  v8::HandleScope scope(env->GetIsolate());
+
+  // Register a debug event listener which sets the break flag and counts.
+  v8::Debug::SetDebugEventListener(env->GetIsolate(), DebugEventCounter);
+  CompileRun("debugger;");
+  CHECK_EQ(1, break_point_hit_count);
+
+  // Check that we ignore debugger statement when breakpoints aren't active.
+  i::Isolate* isolate = reinterpret_cast<i::Isolate*>(env->GetIsolate());
+  isolate->debug()->set_break_points_active(false);
+  CompileRun("debugger;");
+  CHECK_EQ(1, break_point_hit_count);
+}
+
 static const char* kSimpleExtensionSource =
   "(function Foo() {"
   "  return 4;"