fix: crash when focusing WebView webContents (#43921)

fix: crash when focusing WebView

shell/browser/api/electron_api_web_contents.cc

@@ -3339,6 +3339,12 @@ void WebContents::Focus() {
   if (owner_window())
     owner_window()->Focus(true);
 #endif
+
+  // WebView uses WebContentsViewChildFrame, which doesn't have a Focus impl
+  // and triggers a fatal NOTREACHED.
+  if (is_guest())
+    return;
+
   web_contents()->Focus();
 }
 
@@ -3782,7 +3788,8 @@ void WebContents::SetBackgroundColor(std::optional<SkColor> maybe_color) {
 
   content::RenderWidgetHostView* rwhv = rfh->GetView();
   if (rwhv) {
-    // RenderWidgetHostView doesn't allow setting an alpha that's not 0 or 255.
+    // RenderWidgetHostView doesn't allow setting an alpha that's not 0 or
+    // 255.
     rwhv->SetBackgroundColor(is_opaque ? color : SK_ColorTRANSPARENT);
     static_cast<content::RenderWidgetHostViewBase*>(rwhv)
         ->SetContentBackgroundColor(color);

spec/api-web-contents-spec.ts

@@ -1207,6 +1207,22 @@ describe('webContents module', () => {
         expect(currentFocused).to.be.true();
         expect(childFocused).to.be.false();
       });
+
+      it('does not crash when focusing a WebView webContents', async () => {
+        const w = new BrowserWindow({
+          show: false,
+          webPreferences: {
+            nodeIntegration: true,
+            webviewTag: true
+          }
+        });
+
+        w.show();
+        await w.loadURL('data:text/html,<webview src="data:text/html,hi"></webview>');
+
+        const wc = webContents.getAllWebContents().find((wc) => wc.getType() === 'webview')!;
+        expect(() => wc.focus()).to.not.throw();
+      });
     });
 
     const moveFocusToDevTools = async (win: BrowserWindow) => {