[inspector] Return error when paused in different context group

... when trying to resume or step.

BUG=none

Review-Url: https://codereview.chromium.org/2923243002
Cr-Commit-Position: refs/heads/master@{#45747}

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

@@ -1035,9 +1035,7 @@ V8DebuggerAgentImpl::currentAsyncStackTrace() {
 }
 
 bool V8DebuggerAgentImpl::isPaused() const {
-  // TODO(dgozman): this check allows once context group to resume the other,
-  // since they share debugger.
-  return m_debugger->isPaused();
+  return m_debugger->isPausedInContextGroup(m_session->contextGroupId());
 }
 
 void V8DebuggerAgentImpl::didParseSource(

src/inspector/v8-debugger.cc

@@ -198,6 +198,10 @@ void V8Debugger::disable() {
   m_isolate->RestoreOriginalHeapLimit();
 }
 
+bool V8Debugger::isPausedInContextGroup(int contextGroupId) const {
+  return isPaused() && m_pausedContextGroupId == contextGroupId;
+}
+
 bool V8Debugger::enabled() const { return !m_debuggerScript.IsEmpty(); }
 
 void V8Debugger::getCompiledScripts(

src/inspector/v8-debugger.h

@@ -83,6 +83,7 @@ class V8Debugger : public v8::debug::DebugDelegate {
   void disable();
 
   bool isPaused() const { return m_pausedContextGroupId; }
+  bool isPausedInContextGroup(int contextGroupId) const;
   v8::Local<v8::Context> pausedContext() { return m_pausedContext; }
 
   int maxAsyncCallChainDepth() { return m_maxAsyncCallStackDepth; }

test/inspector/debugger/pause-expected.txt

@@ -34,6 +34,39 @@ paused at:
 #var a = 42;
 
 
+Running test: testResumeAnotherGroup
+paused at:
+#var a = 42;
+
+{
+    error : {
+        code : -32000
+        message : Can only perform operation while paused.
+    }
+    id : <messageId>
+}
+{
+    error : {
+        code : -32000
+        message : Can only perform operation while paused.
+    }
+    id : <messageId>
+}
+{
+    error : {
+        code : -32000
+        message : Can only perform operation while paused.
+    }
+    id : <messageId>
+}
+{
+    error : {
+        code : -32000
+        message : Can only perform operation while paused.
+    }
+    id : <messageId>
+}
+
 Running test: testDisableBreaksShouldCancelPause
 paused at:
 #debugger

test/inspector/debugger/pause.js

@@ -82,6 +82,23 @@ InspectorTest.runAsyncTestSuite([
     await Protocol1.Debugger.resume();
   },
 
+  async function testResumeAnotherGroup() {
+    let contextGroup2 = new InspectorTest.ContextGroup();
+    let session2 = contextGroup2.connect();
+    session2.setupScriptMap();
+    let Protocol2 = session2.Protocol;
+    Protocol2.Debugger.enable();
+    Protocol1.Debugger.pause();
+    Protocol1.Runtime.evaluate({expression: 'var a = 42;'});
+    await waitPauseAndDumpLocation(session1);
+    InspectorTest.logMessage(await Protocol2.Debugger.resume());
+    InspectorTest.logMessage(await Protocol2.Debugger.stepOver());
+    InspectorTest.logMessage(await Protocol2.Debugger.stepInto());
+    InspectorTest.logMessage(await Protocol2.Debugger.stepOut());
+    await Protocol1.Debugger.resume();
+    await Protocol2.Debugger.disable();
+  },
+
   async function testDisableBreaksShouldCancelPause() {
     await Protocol1.Debugger.pause();
     await Protocol1.Debugger.setBreakpointsActive({active: false});