Avoid using stale InspectedContext pointers

src/inspector/inspected-context.cc

Index: src/inspector/inspected-context.cc
diff --git a/src/inspector/inspected-context.cc b/src/inspector/inspected-context.cc
index 1b5081ff334ac6be926a6fc0fe29a58e4342a358..82b5a1b5b4e25e5c6bc4f034da8fd8f80939b1db 100644
--- a/src/inspector/inspected-context.cc
+++ b/src/inspector/inspected-context.cc
@@ -75,9 +75,13 @@ v8::Isolate* InspectedContext::isolate() const {
   return m_inspector->isolate();
 }
 
-void InspectedContext::createInjectedScript() {
+bool InspectedContext::createInjectedScript() {
   DCHECK(!m_injectedScript);
-  m_injectedScript = InjectedScript::create(this);
+  std::unique_ptr<InjectedScript> injectedScript = InjectedScript::create(this);
+  // InjectedScript::create can destroy |this|.
+  if (!injectedScript) return false;
+  m_injectedScript = std::move(injectedScript);
+  return true;
 }
 
 void InspectedContext::discardInjectedScript() { m_injectedScript.reset(); }