[inspector] do not resume on agent disable if there is other agents

If there is more then one agent accepts current pause, we should resume
only when last agent is disabled.

R=dgozman@chromium.org

Bug: chromium:834056
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I2904b3f4ab76117511e16450dd575ebf3e20a068
Reviewed-on: https://chromium-review.googlesource.com/1041207Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52931}

src/inspector/v8-debugger-agent-impl.cc

@@ -418,12 +418,10 @@ Response V8DebuggerAgentImpl::disable() {
                       v8::debug::NoBreakOnException);
   m_state->setInteger(DebuggerAgentState::asyncCallStackDepth, 0);
 
-  if (isPaused()) m_debugger->continueProgram(m_session->contextGroupId());
   if (m_breakpointsActive) {
     m_debugger->setBreakpointsActive(false);
     m_breakpointsActive = false;
   }
-  m_debugger->disable();
   m_blackboxedPositions.clear();
   m_blackboxPattern.reset();
   resetBlackboxedStateCache();
@@ -440,6 +438,7 @@ Response V8DebuggerAgentImpl::disable() {
   m_state->remove(DebuggerAgentState::blackboxPattern);
   m_enabled = false;
   m_state->setBoolean(DebuggerAgentState::debuggerEnabled, false);
+  m_debugger->disable();
   return Response::OK();
 }
 

src/inspector/v8-debugger.cc

@@ -184,6 +184,18 @@ void V8Debugger::enable() {
 }
 
 void V8Debugger::disable() {
+  if (isPaused()) {
+    bool scheduledOOMBreak = m_scheduledOOMBreak;
+    bool hasAgentAcceptsPause = false;
+    m_inspector->forEachSession(
+        m_pausedContextGroupId, [&scheduledOOMBreak, &hasAgentAcceptsPause](
+                                    V8InspectorSessionImpl* session) {
+          if (session->debuggerAgent()->acceptsPause(scheduledOOMBreak)) {
+            hasAgentAcceptsPause = true;
+          }
+        });
+    if (!hasAgentAcceptsPause) m_inspector->client()->quitMessageLoopOnPause();
+  }
   if (--m_enableCount) return;
   clearContinueToLocation();
   allAsyncTasksCanceled();

test/inspector/debugger/external-stack-trace.js

@@ -52,6 +52,7 @@ InspectorTest.runAsyncTestSuite([
       InspectorTest.log(
           '> Debugger.enable in another context group returns own debugger id');
     }
+    await Protocol2.Debugger.disable();
   },
 
   async function testInstrumentation() {

test/inspector/sessions/debugger-stepping-and-breakpoints-expected.txt

@@ -226,3 +226,6 @@ Paused in 2:
   hit breakpoints: 
   location: <anonymous>@1
   data: null
+Activating debugger agent in 1
+Disabling debugger agent in 2
+Disabling debugger agent in 1

test/inspector/sessions/debugger-stepping-and-breakpoints.js

@@ -182,6 +182,15 @@ function bar() {
   session2.Protocol.Runtime.evaluate({expression: 'baz();\ndebugger;'});
   await waitForPaused(session2, 2);
 
+  session1.Protocol.Debugger.onResumed(() => InspectorTest.log('session1 is resumed'));
+  session2.Protocol.Debugger.onResumed(() => InspectorTest.log('session2 is resumed'));
+  InspectorTest.log('Activating debugger agent in 1');
+  await session1.Protocol.Debugger.enable();
+  InspectorTest.log('Disabling debugger agent in 2');
+  await session2.Protocol.Debugger.disable();
+  InspectorTest.log('Disabling debugger agent in 1');
+  await session1.Protocol.Debugger.disable();
+
   InspectorTest.completeTest();
 
   function waitForBothPaused() {