fixed removal of requestedFrameId data

lib/frame-tree/content/content-frame-tree.js

@@ -172,7 +172,7 @@ this.frameTree = this.frameTree || (() => {
 			setTimeout(() => sendInitResponse({ framesData: [{ windowId, processed: true }], sessionId }), TIMEOUT_INIT_REQUEST_MESSAGE);
 		});
 		sendInitResponse({ framesData, sessionId, requestedFrameId: doc.documentElement.dataset.requestedFrameId && parentWindowId });
-		delete document.documentElement.dataset.requestedFrameId;
+		delete doc.documentElement.dataset.requestedFrameId;
 	}
 
 	function processFramesSync(doc, frameElements, options, parentWindowId, sessionId) {
@@ -197,7 +197,7 @@ this.frameTree = this.frameTree || (() => {
 			}
 		});
 		sendInitResponse({ framesData, sessionId, requestedFrameId: doc.documentElement.dataset.requestedFrameId && parentWindowId });
-		delete document.documentElement.dataset.requestedFrameId;
+		delete doc.documentElement.dataset.requestedFrameId;
 	}
 
 	function cleanupFrames(frameElements, options, parentWindowId, sessionId) {