Wire Chrome page zoom to Android display size

      level. Confirm that scale of Android app is changed as page zoom
      level is changed in Chrome settings. Note that Android side
      accepts scales from 85% to 150%.

Bug: 810473
Test: Open any Android app. Open Chrome settings and change page zoom
Change-Id: I5af0684f005cfe241c0ad3a7f529ab428f7580c5
Reviewed-on: https://chromium-review.googlesource.com/980073
Commit-Queue: Yuki Awano <yawano@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546758}

chrome/browser/chromeos/arc/intent_helper/arc_settings_service.cc

@@ -19,6 +19,7 @@
 #include "chrome/browser/chromeos/system/timezone_resolver_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profiles_state.h"
+#include "chrome/browser/ui/zoom/chrome_zoom_level_prefs.h"
 #include "chrome/common/chrome_features.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/chromeos_switches.h"
@@ -42,6 +43,7 @@
 #include "components/proxy_config/pref_proxy_config_tracker_impl.h"
 #include "components/proxy_config/proxy_config_dictionary.h"
 #include "components/proxy_config/proxy_config_pref_names.h"
+#include "content/public/common/page_zoom.h"
 #include "net/proxy_resolution/proxy_config.h"
 
 using ::chromeos::CrosSettings;
@@ -127,9 +129,7 @@ class ArcSettingsServiceImpl
   void DefaultNetworkChanged(const chromeos::NetworkState* network) override;
 
  private:
-  PrefService* GetPrefs() const {
-    return Profile::FromBrowserContext(context_)->GetPrefs();
-  }
+  PrefService* GetPrefs() const { return profile_->GetPrefs(); }
 
   // Returns whether kProxy pref proxy config is applied.
   bool IsPrefProxyConfigApplied() const;
@@ -161,6 +161,7 @@ class ArcSettingsServiceImpl
   void SyncBackupEnabled() const;
   void SyncFocusHighlightEnabled() const;
   void SyncFontSize() const;
+  void SyncPageZoom() const;
   void SyncLocale() const;
   void SyncLocationServiceEnabled() const;
   void SyncProxySettings() const;
@@ -198,7 +199,7 @@ class ArcSettingsServiceImpl
   // ConnectionObserver<mojom::AppInstance>:
   void OnConnectionReady() override;
 
-  content::BrowserContext* const context_;
+  Profile* const profile_;
   ArcBridgeService* const arc_bridge_service_;  // Owned by ArcServiceManager.
 
   // Manages pref observation registration.
@@ -207,6 +208,11 @@ class ArcSettingsServiceImpl
   std::unique_ptr<chromeos::CrosSettings::ObserverSubscription>
       reporting_consent_subscription_;
 
+  // Subscription for preference change of default zoom level. Subscription
+  // automatically unregisters a callback when it's destructed.
+  std::unique_ptr<ChromeZoomLevelPrefs::DefaultZoomLevelSubscription>
+      default_zoom_level_subscription_;
+
   base::WeakPtrFactory<ArcSettingsServiceImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ArcSettingsServiceImpl);
@@ -215,9 +221,11 @@ class ArcSettingsServiceImpl
 ArcSettingsServiceImpl::ArcSettingsServiceImpl(
     content::BrowserContext* context,
     ArcBridgeService* arc_bridge_service)
-    : context_(context),
+    : profile_(Profile::FromBrowserContext(context)),
       arc_bridge_service_(arc_bridge_service),
       weak_factory_(this) {
+  DCHECK(profile_);
+
   StartObservingSettingsChanges();
   SyncBootTimeSettings();
   DCHECK(ArcSessionManager::Get());
@@ -338,6 +346,14 @@ void ArcSettingsServiceImpl::StartObservingSettingsChanges() {
       base::Bind(&ArcSettingsServiceImpl::SyncReportingConsent,
                  base::Unretained(this)));
 
+  // It's safe to use base::Unretained. This is unregistered when
+  // default_zoom_level_subscription_ is destructed which is stored as
+  // unique_ptr in member of this class.
+  default_zoom_level_subscription_ =
+      profile_->GetZoomLevelPrefs()->RegisterDefaultZoomLevelCallback(
+          base::BindRepeating(&ArcSettingsServiceImpl::SyncPageZoom,
+                              base::Unretained(this)));
+
   TimezoneSettings::GetInstance()->AddObserver(this);
 
   chromeos::NetworkHandler::Get()->network_state_handler()->AddObserver(
@@ -365,6 +381,7 @@ void ArcSettingsServiceImpl::SyncBootTimeSettings() const {
   SyncAccessibilityVirtualKeyboardEnabled();
   SyncFocusHighlightEnabled();
   SyncFontSize();
+  SyncPageZoom();
   SyncProxySettings();
   SyncReportingConsent();
   SyncSelectToSpeakEnabled();
@@ -465,6 +482,15 @@ void ArcSettingsServiceImpl::SyncFontSize() const {
                         extras);
 }
 
+void ArcSettingsServiceImpl::SyncPageZoom() const {
+  double zoom_level = profile_->GetZoomLevelPrefs()->GetDefaultZoomLevelPref();
+  double zoom_factor = content::ZoomLevelToZoomFactor(zoom_level);
+
+  base::DictionaryValue extras;
+  extras.SetDouble("zoomFactor", zoom_factor);
+  SendSettingsBroadcast("org.chromium.arc.intent_helper.SET_PAGE_ZOOM", extras);
+}
+
 void ArcSettingsServiceImpl::SyncLocale() const {
   const PrefService::Preference* pref =
       registrar_.prefs()->FindPreference(::prefs::kApplicationLocale);