[Nearby] Add 'Clear Prefs' button to chrome://nearby-internals.

Adds a 'Clear Prefs' button to the logging tab of
chrome://nearby-internals, as follows:
https://screenshot.googleplex.com/Sq39758XDgUw8NE which resets
the Nearby feature, as follows:
1. before: https://screenshot.googleplex.com/7WoBN4GYggS5UPf,
   https://screenshot.googleplex.com/6ERnEmwWJCzEwYm
2. after: https://screenshot.googleplex.com/jaVKuB9nLrqFYfd
and adds a log message to notify users that the prefs have been
cleared.

(cherry picked from commit 4c1213c)

Fixed: 1147242
Change-Id: Ib666124b0c63df66eace9a8a0af26da8670cbccf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2817842
Commit-Queue: Juliet Levesque <julietlevesque@google.com>
Reviewed-by: Josh Nohle <nohle@chromium.org>
Reviewed-by: James Vecore <vecore@google.com>
Cr-Original-Commit-Position: refs/heads/master@{#871501}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2826156
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/branch-heads/4472@{#83}
Cr-Branched-From: 3d60439-refs/heads/master@{#870763}

chrome/browser/resources/nearby_internals/BUILD.gn

@@ -37,6 +37,7 @@ preprocess_if_expr("preprocess") {
     "nearby_contact_browser_proxy.js",
     "nearby_http_browser_proxy.js",
     "nearby_logs_browser_proxy.js",
+    "nearby_prefs_browser_proxy.js",
     "nearby_ui_trigger_browser_proxy.js",
     "types.js",
   ]
@@ -91,6 +92,7 @@ js_type_check("closure_compile") {
     ":nearby_http_browser_proxy",
     ":nearby_internals",
     ":nearby_logs_browser_proxy",
+    ":nearby_prefs_browser_proxy",
     ":nearby_ui_trigger_browser_proxy",
     ":types",
     ":ui_trigger_list_object",
@@ -109,6 +111,7 @@ js_library("nearby_internals") {
     ":nearby_contact_browser_proxy",
     ":nearby_http_browser_proxy",
     ":nearby_logs_browser_proxy",
+    ":nearby_prefs_browser_proxy",
     ":nearby_ui_trigger_browser_proxy",
     ":types",
     ":ui_trigger_list_object",
@@ -122,6 +125,7 @@ js_library("logging_tab") {
   deps = [
     ":log_object",
     ":nearby_logs_browser_proxy",
+    ":nearby_prefs_browser_proxy",
     ":types",
     "//third_party/polymer/v3_0/components-chromium/polymer:polymer_bundled",
     "//ui/webui/resources/js:cr.m",
@@ -144,6 +148,13 @@ js_library("nearby_logs_browser_proxy") {
   ]
 }
 
+js_library("nearby_prefs_browser_proxy") {
+  deps = [
+    ":types",
+    "//ui/webui/resources/js:cr.m",
+  ]
+}
+
 js_library("nearby_http_browser_proxy") {
   deps = [
     ":types",

chrome/browser/resources/nearby_internals/logging_tab.html

@@ -28,6 +28,10 @@
     on-click="onClearLogsButtonClicked_">
   Clear Logs
 </cr-button>
+<cr-button class="internals-button"
+    on-click="onClearPrefsButtonClicked_">
+  Reset Nearby
+</cr-button>
 <iron-list items="[[logList_]]" as="log" id="logs-list">
   <template>
     <log-object log-message="[[log]]">

chrome/browser/resources/nearby_internals/logging_tab.js

@@ -11,6 +11,7 @@ import './shared_style.js';
 import {WebUIListenerBehavior} from 'chrome://resources/js/web_ui_listener_behavior.m.js';
 import {html, Polymer} from 'chrome://resources/polymer/v3_0/polymer/polymer_bundled.min.js';
 import {NearbyLogsBrowserProxy} from './nearby_logs_browser_proxy.js';
+import {NearbyPrefsBrowserProxy} from './nearby_prefs_browser_proxy.js';
 import {LogMessage, Severity} from './types.js';
 
 /**
@@ -65,12 +66,16 @@ Polymer({
   /** @private {?NearbyLogsBrowserProxy}*/
   browserProxy_: null,
 
+  /** @private {?NearbyPrefsBrowserProxy}*/
+  prefsBrowserProxy_: null,
+
   /**
    * Initialize |browserProxy_| and |logList_|.
    * @override
    */
   created() {
     this.browserProxy_ = NearbyLogsBrowserProxy.getInstance();
+    this.prefsBrowserProxy_ = NearbyPrefsBrowserProxy.getInstance();
   },
 
   /**
@@ -95,6 +100,14 @@ Polymer({
     this.clearLogBuffer_();
   },
 
+  /**
+   * Clears Nearby Share Prefs.
+   * @private
+   */
+  onClearPrefsButtonClicked_() {
+    this.prefsBrowserProxy_.clearNearbyPrefs();
+  },
+
   /**
    * Saves and downloads javascript logs that appear on the page.
    * @private

chrome/browser/resources/nearby_internals/nearby_prefs_browser_proxy.js

@@ -0,0 +1,20 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import {addSingletonGetter} from 'chrome://resources/js/cr.m.js';
+
+/**
+ * JavaScript hooks into the native WebUI handler to communicate with C++ about
+ * Nearby prefs.
+ */
+export class NearbyPrefsBrowserProxy {
+  /**
+   * Tells C++ side to clear Nearby Prefs.
+   */
+  clearNearbyPrefs() {
+    chrome.send('clearNearbyPrefs');
+  }
+}
+
+addSingletonGetter(NearbyPrefsBrowserProxy);

chrome/browser/ui/BUILD.gn

@@ -2508,6 +2508,8 @@ static_library("ui") {
       "webui/nearby_internals/nearby_internals_http_handler.h",
       "webui/nearby_internals/nearby_internals_logs_handler.cc",
       "webui/nearby_internals/nearby_internals_logs_handler.h",
+      "webui/nearby_internals/nearby_internals_prefs_handler.cc",
+      "webui/nearby_internals/nearby_internals_prefs_handler.h",
       "webui/nearby_internals/nearby_internals_ui.cc",
       "webui/nearby_internals/nearby_internals_ui.h",
       "webui/nearby_internals/nearby_internals_ui_trigger_handler.cc",

chrome/browser/ui/webui/nearby_internals/nearby_internals_prefs_handler.cc

@@ -0,0 +1,48 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/ui/webui/nearby_internals/nearby_internals_prefs_handler.h"
+#include "base/bind.h"
+#include "chrome/browser/nearby_sharing/common/nearby_share_prefs.h"
+#include "chrome/browser/nearby_sharing/logging/logging.h"
+#include "chrome/browser/profiles/profile.h"
+
+namespace {
+
+const char kNearbySharingPrefPrefix[] = "nearby_sharing";
+
+}  // namespace
+
+NearbyInternalsPrefsHandler::NearbyInternalsPrefsHandler(
+    content::BrowserContext* context) {
+  Profile* profile = Profile::FromBrowserContext(context);
+  pref_service_ = profile->GetPrefs();
+}
+
+NearbyInternalsPrefsHandler::~NearbyInternalsPrefsHandler() = default;
+
+void NearbyInternalsPrefsHandler::RegisterMessages() {
+  web_ui()->RegisterMessageCallback(
+      "clearNearbyPrefs",
+      base::BindRepeating(&NearbyInternalsPrefsHandler::HandleClearNearbyPrefs,
+                          base::Unretained(this)));
+}
+
+void NearbyInternalsPrefsHandler::OnJavascriptAllowed() {}
+
+void NearbyInternalsPrefsHandler::OnJavascriptDisallowed() {}
+
+void NearbyInternalsPrefsHandler::HandleClearNearbyPrefs(
+    const base::ListValue* args) {
+  // Turn Nearby feature off.
+  pref_service_->SetBoolean(prefs::kNearbySharingEnabledPrefName, false);
+
+  // Clear all Nearby related prefs.
+  pref_service_->ClearPrefsWithPrefixSilently(kNearbySharingPrefPrefix);
+
+  // Add log message so users who trigger the Clear Pref button on
+  // chrome://nearby-internals know that the Nearby prefs have been cleared.
+  NS_LOG(INFO)
+      << "Nearby Share has been disabled and Nearby prefs have been cleared.";
+}

chrome/browser/ui/webui/nearby_internals/nearby_internals_prefs_handler.h

@@ -0,0 +1,40 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+#ifndef CHROME_BROWSER_UI_WEBUI_NEARBY_INTERNALS_NEARBY_INTERNALS_PREFS_HANDLER_H_
+#define CHROME_BROWSER_UI_WEBUI_NEARBY_INTERNALS_NEARBY_INTERNALS_PREFS_HANDLER_H_
+
+#include "base/memory/weak_ptr.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/browser/web_ui_message_handler.h"
+
+namespace content {
+class BrowserContext;
+}  // namespace content
+
+// WebUIMessageHandler for Nearby Prefs to allow users to Clear Prefs from the
+// chrome://nearby-internals logging tab.
+class NearbyInternalsPrefsHandler : public content::WebUIMessageHandler {
+ public:
+  explicit NearbyInternalsPrefsHandler(content::BrowserContext* context);
+  NearbyInternalsPrefsHandler(const NearbyInternalsPrefsHandler&) = delete;
+  NearbyInternalsPrefsHandler& operator=(const NearbyInternalsPrefsHandler&) =
+      delete;
+  ~NearbyInternalsPrefsHandler() override;
+
+  // content::WebUIMessageHandler
+  void RegisterMessages() override;
+  void OnJavascriptAllowed() override;
+  void OnJavascriptDisallowed() override;
+
+ private:
+  // Message handler callback that clears Nearby prefs in order to put the user
+  // back into a state of before they have touched the feature.
+  void HandleClearNearbyPrefs(const base::ListValue* args);
+
+  PrefService* pref_service_ = nullptr;
+
+  base::WeakPtrFactory<NearbyInternalsPrefsHandler> weak_ptr_factory_{this};
+};
+
+#endif  // CHROME_BROWSER_UI_WEBUI_NEARBY_INTERNALS_NEARBY_INTERNALS_PREFS_HANDLER_H_

chrome/browser/ui/webui/nearby_internals/nearby_internals_ui.cc

@@ -13,6 +13,7 @@
 #include "chrome/browser/ui/webui/nearby_internals/nearby_internals_contact_handler.h"
 #include "chrome/browser/ui/webui/nearby_internals/nearby_internals_http_handler.h"
 #include "chrome/browser/ui/webui/nearby_internals/nearby_internals_logs_handler.h"
+#include "chrome/browser/ui/webui/nearby_internals/nearby_internals_prefs_handler.h"
 #include "chrome/browser/ui/webui/nearby_internals/nearby_internals_ui_trigger_handler.h"
 #include "chrome/browser/ui/webui/webui_util.h"
 #include "chrome/common/webui_url_constants.h"
@@ -48,6 +49,8 @@ NearbyInternalsUI::NearbyInternalsUI(content::WebUI* web_ui)
       std::make_unique<NearbyInternalsContactHandler>(context));
   web_ui->AddMessageHandler(
       std::make_unique<NearbyInternalsHttpHandler>(context));
+  web_ui->AddMessageHandler(
+      std::make_unique<NearbyInternalsPrefsHandler>(context));
   web_ui->AddMessageHandler(
       std::make_unique<NearbyInternalsUiTriggerHandler>(context));
 }