[Chromecast] Add localStorage APIs to mojom::CastWebService

Exposes these methods so they can be called over IPC.

Bug: b/149041392
Test: Cast CQ
Change-Id: I06b9d292c53d573ea27c851ea06290e35c889953
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3218129
Reviewed-by: Alex Gough <ajgo@chromium.org>
Commit-Queue: Sean Topping <seantopping@chromium.org>
Cr-Commit-Position: refs/heads/main@{#930354}

chromecast/browser/cast_web_service.cc

@@ -89,7 +89,7 @@ void CastWebService::FlushDomLocalStorage() {
       }));
 }
 
-void CastWebService::ClearLocalStorage(base::OnceClosure callback) {
+void CastWebService::ClearLocalStorage(ClearLocalStorageCallback callback) {
   browser_context_->ForEachStoragePartition(
       base::BindRepeating(
           [](base::OnceClosure cb, content::StoragePartition* partition) {

chromecast/browser/cast_web_service.h

@@ -69,19 +69,15 @@ class CastWebService : public mojom::CastWebService,
     return overlay_renderer_cache_.get();
   }
 
-  void FlushDomLocalStorage();
-
-  // |callback| is called when data deletion is done or at least the deletion
-  // is scheduled.
-  void ClearLocalStorage(base::OnceClosure callback);
-
   // mojom::CastWebService implementation:
   void CreateWebView(
       mojom::CastWebViewParamsPtr params,
       mojo::PendingReceiver<mojom::CastWebContents> web_contents,
       mojo::PendingReceiver<mojom::CastContentWindow> window) override;
   void RegisterWebUiClient(mojo::PendingRemote<mojom::WebUiClient> client,
                            const std::vector<std::string>& hosts) override;
+  void FlushDomLocalStorage() override;
+  void ClearLocalStorage(ClearLocalStorageCallback callback) override;
 
   // mojom::BrowserIdentificationSettingsManager implementation:
   void CreateSessionWithSubstitutions(

chromecast/browser/mojom/cast_web_service.mojom

@@ -163,5 +163,12 @@ interface CastWebService {
   // for details on how Web UIs are used in the Cast Browser.
   RegisterWebUiClient(pending_remote<WebUiClient> client,
                       array<string> hosts);
+
+  // Write all DOM localStorage to disk.
+  FlushDomLocalStorage();
+
+  // Clears all localStorage data from the device. The response callback is
+  // called when data deletion is done.
+  ClearLocalStorage() => ();
 };