[inspector] return meaningful error on Debug.setScriptSource for ES module

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

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/inspector/v8-debugger-agent-impl.h"
 
 #include <algorithm>
 
 #include "src/debug/debug-interface.h"
 #include "src/inspector/injected-script.h"
@@ skipping 504 matching lines @@
   return Response::OK();
 }
 
 Response V8DebuggerAgentImpl::setScriptSource(
     const String16& scriptId, const String16& newContent, Maybe<bool> dryRun,
     Maybe<protocol::Array<protocol::Debugger::CallFrame>>* newCallFrames,
     Maybe<bool>* stackChanged, Maybe<StackTrace>* asyncStackTrace,
     Maybe<protocol::Runtime::ExceptionDetails>* optOutCompileError) {
   if (!enabled()) return Response::Error(kDebuggerNotEnabled);
 
+  ScriptsMap::iterator it = m_scripts.find(scriptId);
+  if (it == m_scripts.end()) {
+    return Response::Error("No script with given id found");
+  }
+  if (it->second->isModule()) {
+    // TODO(kozyatinskiy): LiveEdit should support ES6 module
+    return Response::Error("Editing module's script is not supported.");
+  }
+
   v8::HandleScope handles(m_isolate);
   v8::Local<v8::String> newSource = toV8String(m_isolate, newContent);
   bool compileError = false;
   Response response = m_debugger->setScriptSource(
       scriptId, newSource, dryRun.fromMaybe(false), optOutCompileError,
       &m_pausedCallFrames, stackChanged, &compileError);
   if (!response.isSuccess() || compileError) return response;
 
-  ScriptsMap::iterator it = m_scripts.find(scriptId);
-  if (it != m_scripts.end()) it->second->setSource(newSource);
-
+  it->second->setSource(newSource);
   std::unique_ptr<Array<CallFrame>> callFrames;
   response = currentCallFrames(&callFrames);
   if (!response.isSuccess()) return response;
   *newCallFrames = std::move(callFrames);
   *asyncStackTrace = currentAsyncStackTrace();
   return Response::OK();
 }
 
 Response V8DebuggerAgentImpl::restartFrame(
     const String16& callFrameId,
@@ skipping 624 matching lines @@
 void V8DebuggerAgentImpl::reset() {
   if (!enabled()) return;
   m_scheduledDebuggerStep = NoStep;
   m_blackboxedPositions.clear();
   resetBlackboxedStateCache();
   m_scripts.clear();
   m_breakpointIdToDebuggerBreakpointIds.clear();
 }
 
 }  // namespace v8_inspector