2 files changed, 8 insertions, 4 deletions
diff --git a/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.cpp b/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.cpp
index cee73f1ed38..41b43b7972a 100644
--- a/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.cpp
+++ b/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.cpp
@@ -16,6 +16,7 @@
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "platform/PlatformResourceLoader.h"
+#include "base/logging.h"
 
 namespace blink {
 
@@ -53,9 +54,12 @@ static v8::Local<v8::Value> compileAndRunPrivateScript(ScriptState* scriptState,
 
     v8::Local<v8::Context> context = scriptState->context();
     v8::Local<v8::Object> global = context->Global();
-    v8::Local<v8::Value> privateScriptController = global->Get(context, v8String(isolate, "privateScriptController")).ToLocalChecked();
-    RELEASE_ASSERT(privateScriptController->IsUndefined() || privateScriptController->IsObject());
-    if (privateScriptController->IsObject()) {
+    v8::Local<v8::String> key = v8String(isolate, "privateScriptController");
+
+    if (global->HasOwnProperty(context, key).FromJust()) {
+        v8::Local<v8::Value> privateScriptController =
+            global->Get(context, key).ToLocalChecked();
+        CHECK(privateScriptController->IsObject());
         v8::Local<v8::Object> privateScriptControllerObject = privateScriptController.As<v8::Object>();
         v8::Local<v8::Value> importFunctionValue = privateScriptControllerObject->Get(context, v8String(isolate, "import")).ToLocalChecked();
         if (importFunctionValue->IsUndefined()) {
diff --git a/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.js b/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.js
index 9dc27f0d7df..6010df9963b 100644
--- a/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.js
+++ b/chromium/third_party/WebKit/Source/bindings/core/v8/PrivateScriptRunner.js
@@ -136,7 +136,7 @@ PrivateScriptController.prototype = {
     },
 }
 
-if (typeof window.privateScriptController === 'undefined')
+if (!window.hasOwnProperty("privateScriptController"))
     window.privateScriptController = new PrivateScriptController();
 
 // This line must be the last statement of this JS file.