[inspector] better isArrayLike for injected-script-source.js

src/inspector/v8-injected-script-host.cc

Index: src/inspector/v8-injected-script-host.cc
diff --git a/src/inspector/v8-injected-script-host.cc b/src/inspector/v8-injected-script-host.cc
index 80c256fcb30d611f22ad7339693226d60a079420..07c7740e38d2d7fe5202e420822e55a3a6616505 100644
--- a/src/inspector/v8-injected-script-host.cc
+++ b/src/inspector/v8-injected-script-host.cc
@@ -58,6 +58,8 @@ v8::Local<v8::Object> V8InjectedScriptHost::create(
   setFunctionProperty(context, injectedScriptHost, "nullifyPrototype",
                       V8InjectedScriptHost::nullifyPrototypeCallback,
                       debuggerExternal);
+  setFunctionProperty(context, injectedScriptHost, "get",
+                      V8InjectedScriptHost::getCallback, debuggerExternal);
   setFunctionProperty(context, injectedScriptHost, "internalConstructorName",
                       V8InjectedScriptHost::internalConstructorNameCallback,
                       debuggerExternal);
@@ -90,6 +92,24 @@ void V8InjectedScriptHost::nullifyPrototypeCallback(
       .ToChecked();
 }
 
+void V8InjectedScriptHost::getCallback(
+    const v8::FunctionCallbackInfo<v8::Value>& info) {
+  CHECK(info.Length() == 2 && info[1]->IsString());
+  if (!info[0]->IsObject()) return;
+  v8::Isolate* isolate = info.GetIsolate();
+  v8::Local<v8::Context> context = isolate->GetCurrentContext();
+  v8::TryCatch tryCatch(isolate);
+  v8::Isolate::DisallowJavascriptExecutionScope throwJs(
+      isolate, v8::Isolate::DisallowJavascriptExecutionScope::THROW_ON_FAILURE);
+  v8::Local<v8::Value> property;
+  if (info[0]
+          .As<v8::Object>()
+          ->Get(context, v8::Local<v8::String>::Cast(info[1]))
+          .ToLocal(&property)) {
+    info.GetReturnValue().Set(property);

[dgozman, 2017/03/23 21:10:20]

So, do we return undefined in case of JS execution or exception?

[kozy, 2017/03/24 00:40:37]

yes, we do, in current use cases it looks like expected behavior.

+  }
+}
+
 void V8InjectedScriptHost::internalConstructorNameCallback(
     const v8::FunctionCallbackInfo<v8::Value>& info) {
   if (info.Length() < 1 || !info[0]->IsObject()) return;