[Search] Add a policy to allow disabling a search feature

Specifically, Contextual Search can now be controlled by policy.

BUG=432631

Review URL: https://codereview.chromium.org/720933002

Cr-Commit-Position: refs/heads/master@{#304662}

chrome/android/java/src/org/chromium/chrome/browser/preferences/PrefServiceBridge.java

@@ -361,6 +361,14 @@ public boolean isContextualSearchDisabled() {
         return getContextualSearchPreference().equals(CONTEXTUAL_SEARCH_DISABLED);
     }
 
+    /**
+     * @return whether the Contextual Search feature is disabled by policy.
+     */
+    public boolean isContextualSearchDisabledByPolicy() {
+        return nativeGetContextualSearchPreferenceIsManaged()
+                && isContextualSearchDisabled();
+    }
+
     /**
      * @return whether the Contextual Search feature is uninitialized (preference unset by the
      *         user).
@@ -734,6 +742,7 @@ private native void nativeClearBrowsingData(boolean history, boolean cache,
     private native void nativeGetProfilePath(ProfilePathCallback callback);
     private native void nativeSetContextualSearchPreference(String preference);
     private native String nativeGetContextualSearchPreference();
+    private native boolean nativeGetContextualSearchPreferenceIsManaged();
     private native boolean nativeGetSearchSuggestEnabled();
     private native void nativeSetSearchSuggestEnabled(boolean enabled);
     private native boolean nativeGetSearchSuggestManaged();

chrome/browser/android/preferences/pref_service_bridge.cc

@@ -545,6 +545,11 @@ static jstring GetContextualSearchPreference(JNIEnv* env, jobject obj) {
           Release();
 }
 
+static jboolean GetContextualSearchPreferenceIsManaged(JNIEnv* env,
+                                                       jobject obj) {
+  return GetPrefService()->IsManagedPreference(prefs::kContextualSearchEnabled);
+}
+
 static void SetContextualSearchPreference(JNIEnv* env, jobject obj,
                                           jstring pref) {
   GetPrefService()->SetString(prefs::kContextualSearchEnabled,

chrome/browser/policy/configuration_policy_handler_list_factory.cc

@@ -27,6 +27,10 @@
 #include "components/translate/core/common/translate_pref_names.h"
 #include "policy/policy_constants.h"
 
+#if defined(OS_ANDROID)
+#include "chrome/browser/search/contextual_search_policy_handler_android.h"
+#endif
+
 #if !defined(OS_IOS)
 #include "chrome/browser/net/disk_cache_dir_policy_handler.h"
 #include "chrome/browser/policy/file_selection_dialogs_policy_handler.h"
@@ -575,6 +579,11 @@ scoped_ptr<ConfigurationPolicyHandlerList> BuildHandlerList(
   handlers->AddHandler(make_scoped_ptr<ConfigurationPolicyHandler>(
       new URLBlacklistPolicyHandler()));
 
+#if defined(OS_ANDROID)
+  handlers->AddHandler(make_scoped_ptr<ConfigurationPolicyHandler>(
+      new ContextualSearchPolicyHandlerAndroid()));
+#endif
+
 #if !defined(OS_IOS)
   handlers->AddHandler(make_scoped_ptr<ConfigurationPolicyHandler>(
       new FileSelectionDialogsPolicyHandler()));

chrome/browser/search/contextual_search_policy_handler_android.cc

@@ -0,0 +1,39 @@
+// Copyright 2014 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/search/contextual_search_policy_handler_android.h"
+
+#include "base/prefs/pref_value_map.h"
+#include "base/values.h"
+#include "chrome/common/pref_names.h"
+#include "components/policy/core/common/policy_map.h"
+#include "policy/policy_constants.h"
+
+namespace policy {
+
+ContextualSearchPolicyHandlerAndroid::ContextualSearchPolicyHandlerAndroid()
+    : TypeCheckingPolicyHandler(key::kContextualSearchEnabled,
+                                base::Value::TYPE_BOOLEAN) {}
+
+ContextualSearchPolicyHandlerAndroid::~ContextualSearchPolicyHandlerAndroid() {
+}
+
+void ContextualSearchPolicyHandlerAndroid::ApplyPolicySettings(
+    const PolicyMap& policies,
+    PrefValueMap* prefs) {
+  const base::Value* value = policies.GetValue(policy_name());
+  bool contextual_search_enabled = true;
+  // From a Contextual Search preference point of view, "false" means the
+  // feature is turned off completely. "" means the feature is uninitialized and
+  // an opt-in screen is presented to the user, after which the preference is
+  // either "true" or "false", depending on their choice. Here a false policy
+  // explicitly disables Contextual Search.
+  if (value &&
+      value->GetAsBoolean(&contextual_search_enabled) &&
+      !contextual_search_enabled) {
+    prefs->SetString(prefs::kContextualSearchEnabled, "false");
+  }
+}
+
+}  // namespace policy

chrome/browser/search/contextual_search_policy_handler_android.h

@@ -0,0 +1,31 @@
+// Copyright 2014 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_SEARCH_CONTEXTUAL_SEARCH_POLICY_HANDLER_ANDROID_H_
+#define CHROME_BROWSER_SEARCH_CONTEXTUAL_SEARCH_POLICY_HANDLER_ANDROID_H_
+
+#include "components/policy/core/browser/configuration_policy_handler.h"
+
+namespace policy {
+
+class PolicyMap;
+
+// ConfigurationPolicyHandler for the ContextualSearchEnabled policy.
+class ContextualSearchPolicyHandlerAndroid
+  : public TypeCheckingPolicyHandler {
+ public:
+  ContextualSearchPolicyHandlerAndroid();
+  ~ContextualSearchPolicyHandlerAndroid() override;
+
+  // ConfigurationPolicyHandler methods:
+  void ApplyPolicySettings(const PolicyMap& policies,
+                           PrefValueMap* prefs) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ContextualSearchPolicyHandlerAndroid);
+};
+
+}  // namespace policy
+
+#endif  // CHROME_BROWSER_SEARCH_CONTEXTUAL_SEARCH_POLICY_HANDLER_ANDROID_H_

chrome/browser/search/contextual_search_policy_handler_android_unittest.cc

@@ -0,0 +1,59 @@
+// Copyright 2014 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 "base/prefs/pref_value_map.h"
+#include "base/values.h"
+#include "chrome/browser/search/contextual_search_policy_handler_android.h"
+#include "chrome/common/pref_names.h"
+#include "components/policy/core/common/policy_map.h"
+#include "policy/policy_constants.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace policy {
+
+TEST(ContextualSearchPolicyHandlerAndroidTest, Default) {
+  PolicyMap policy;
+  PrefValueMap prefs;
+  ContextualSearchPolicyHandlerAndroid handler;
+  handler.ApplyPolicySettings(policy, &prefs);
+  std::string pref_value;
+  EXPECT_FALSE(prefs.GetString(prefs::kContextualSearchEnabled, &pref_value));
+  EXPECT_EQ("", pref_value);
+}
+
+TEST(ContextualSearchPolicyHandlerAndroidTest, Enabled) {
+  PolicyMap policy;
+  policy.Set(key::kContextualSearchEnabled,
+             POLICY_LEVEL_MANDATORY,
+             POLICY_SCOPE_USER,
+             new base::FundamentalValue(true),
+             NULL);
+  PrefValueMap prefs;
+  ContextualSearchPolicyHandlerAndroid handler;
+  handler.ApplyPolicySettings(policy, &prefs);
+
+  // Enabling Contextual Search policy should not set the pref.
+  std::string pref_value;
+  EXPECT_FALSE(prefs.GetString(prefs::kContextualSearchEnabled, &pref_value));
+  EXPECT_EQ("", pref_value);
+}
+
+TEST(ContextualSearchPolicyHandlerAndroidTest, Disabled) {
+  PolicyMap policy;
+  policy.Set(key::kContextualSearchEnabled,
+             POLICY_LEVEL_MANDATORY,
+             POLICY_SCOPE_USER,
+             new base::FundamentalValue(false),
+             NULL);
+  PrefValueMap prefs;
+  ContextualSearchPolicyHandlerAndroid handler;
+  handler.ApplyPolicySettings(policy, &prefs);
+
+  // Disabling Contextual Search should switch the pref to managed.
+  std::string pref_value;
+  EXPECT_TRUE(prefs.GetString(prefs::kContextualSearchEnabled, &pref_value));
+  EXPECT_EQ("false", pref_value);
+}
+
+}  // namespace policy

chrome/chrome_browser.gypi

@@ -583,6 +583,8 @@
       'browser/safe_browsing/safe_browsing_tab_observer.h',
       'browser/safe_browsing/srt_global_error_win.cc',
       'browser/safe_browsing/srt_global_error_win.h',
+      'browser/search/contextual_search_policy_handler_android.cc',
+      'browser/search/contextual_search_policy_handler_android.h',
       'browser/search/contextual_search_promo_source_android.cc',
       'browser/search/contextual_search_promo_source_android.h',
       'browser/search/iframe_source.cc',

chrome/chrome_tests_unit.gypi

@@ -692,6 +692,7 @@
       'browser/safe_browsing/safe_browsing_store_unittest.cc',
       'browser/safe_browsing/safe_browsing_util_unittest.cc',
       'browser/safe_browsing/two_phase_uploader_unittest.cc',
+      'browser/search/contextual_search_policy_handler_android_unittest.cc',
       'browser/search/hotword_service_unittest.cc',
       'browser/search/iframe_source_unittest.cc',
       'browser/search/instant_service_unittest.cc',

chrome/test/data/policy/policy_test_cases.json

@@ -353,6 +353,10 @@
     ]
   },
 
+  "ContextualSearchEnabled": {
+    "os": ["android"]
+  },
+
   "AutoFillEnabled": {
     "os": ["win", "linux", "mac", "chromeos"],
     "can_be_recommended": true,

components/policy/resources/policy_templates.json

@@ -123,7 +123,7 @@
 #   persistent IDs for all fields (but not for groups!) are needed. These are
 #   specified by the 'id' keys of each policy. NEVER CHANGE EXISTING IDs,
 #   because doing so would break the deployed wire format!
-#   For your editing convenience: highest ID currently used: 280
+#   For your editing convenience: highest ID currently used: 281
 #
 # Placeholders:
 #   The following placeholder strings are automatically substituted:
@@ -6955,6 +6955,28 @@
 
       Note that, despite the number, "sslv3" is an earier version than "tls1".''',
     },
+    {
+      'name': 'ContextualSearchEnabled',
+      'type': 'main',
+      'schema': { 'type': 'boolean' },
+      'supported_on': [
+        'android:40-',
+      ],
+      'features': {
+        'dynamic_refresh': True,
+        'per_profile': True,
+      },
+      'example_value': True,
+      'id': 281,
+      'caption': '''Enable Touch to Search''',
+      'desc': '''Enables the availability of Touch to Search in <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph>'s content view.
+
+      If you enable this setting, Touch to Search will be available to the user and they can choose to turn the feature on or off.
+
+      If you disable this setting, Touch to Search will be disabled completely.
+
+      If this policy is left not set, it is equivalent to being enabled, see description above.''',
+    },
   ],
   'messages': {
     # Messages that are not associated to any policies.

tools/metrics/histograms/histograms.xml

@@ -43774,6 +43774,8 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="278" label="Extension Settings"/>
   <int value="279" label="SSL minimum version"/>
   <int value="280" label="SSL fallback minimum version"/>
+  <int value="281"
+      label="Control the availability of the Contextual Search feature."/>
 </enum>
 
 <enum name="EnterprisePolicyInvalidations" type="int">