Adds magnifier boiler plate

This change:
- adds the ability to swap between Autoclick and Magnifier in the same accessibility_common extension
- fixes the accessibility_common_manifest_guest.json path; accessibility_common was actually not being loaded when using guest manifests (e.g. login screen)
- adds starter class for magnifier

R=katie@chromium.org

AX-Relnotes: n/a
Test: toggle all states of autoclick and magnifier: 0, 0; 0, 1; 1,0; 1,1. Verify the correct accessibilityCommon.autoclick_ and accessibilityCommon.magnifier_ objects get nullified/set and that the extension gets unloaded with 0,0. Automated tests tbd.
Change-Id: I5bf2c25dd1a65403c07c5941c48129cd8ad86a1b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2325131
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Katie Dektar <katie@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792857}

chrome/browser/chromeos/accessibility/accessibility_common_browsertest.cc

+// Copyright 2020 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 "ash/public/cpp/ash_pref_names.h"
+#include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
+#include "chrome/browser/extensions/component_loader.h"
+#include "chrome/browser/extensions/extension_service.h"
+#include "chrome/common/extensions/extension_constants.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "components/prefs/pref_service.h"
+#include "content/public/test/browser_test.h"
+#include "content/public/test/test_utils.h"
+#include "extensions/browser/extension_system.h"
+#include "extensions/browser/notification_types.h"
+
+namespace chromeos {
+
+class AccessibilityCommonTest : public InProcessBrowserTest {
+ public:
+  bool DoesComponentExtensionExist(const std::string& id) {
+    return extensions::ExtensionSystem::Get(
+               AccessibilityManager::Get()->profile())
+        ->extension_service()
+        ->component_loader()
+        ->Exists(id);
+  }
+
+ protected:
+  AccessibilityCommonTest() = default;
+};
+
+IN_PROC_BROWSER_TEST_F(AccessibilityCommonTest, ToggleFeatures) {
+  AccessibilityManager* manager = AccessibilityManager::Get();
+  const auto& enabled_features =
+      manager->GetAccessibilityCommonEnabledFeaturesForTest();
+
+  EXPECT_TRUE(enabled_features.empty());
+  EXPECT_FALSE(DoesComponentExtensionExist(
+      extension_misc::kAccessibilityCommonExtensionId));
+
+  PrefService* pref_service = manager->profile()->GetPrefs();
+
+  content::WindowedNotificationObserver
+      accessibility_common_extension_load_waiter(
+          extensions::NOTIFICATION_EXTENSION_HOST_DID_STOP_FIRST_LOAD,
+          content::NotificationService::AllSources());
+  pref_service->SetBoolean(ash::prefs::kAccessibilityAutoclickEnabled, true);
+  accessibility_common_extension_load_waiter.Wait();
+
+  EXPECT_EQ(1U, enabled_features.size());
+  EXPECT_EQ(1U,
+            enabled_features.count(ash::prefs::kAccessibilityAutoclickEnabled));
+  EXPECT_TRUE(DoesComponentExtensionExist(
+      extension_misc::kAccessibilityCommonExtensionId));
+
+  pref_service->SetBoolean(ash::prefs::kAccessibilityScreenMagnifierEnabled,
+                           true);
+  EXPECT_EQ(2U, enabled_features.size());
+  EXPECT_EQ(1U,
+            enabled_features.count(ash::prefs::kAccessibilityAutoclickEnabled));
+  EXPECT_EQ(1U, enabled_features.count(
+                    ash::prefs::kAccessibilityScreenMagnifierEnabled));
+  EXPECT_TRUE(DoesComponentExtensionExist(
+      extension_misc::kAccessibilityCommonExtensionId));
+
+  pref_service->SetBoolean(ash::prefs::kAccessibilityAutoclickEnabled, false);
+  EXPECT_EQ(1U, enabled_features.size());
+  EXPECT_EQ(1U, enabled_features.count(
+                    ash::prefs::kAccessibilityScreenMagnifierEnabled));
+  EXPECT_TRUE(DoesComponentExtensionExist(
+      extension_misc::kAccessibilityCommonExtensionId));
+
+  pref_service->SetBoolean(ash::prefs::kAccessibilityScreenMagnifierEnabled,
+                           false);
+  EXPECT_TRUE(enabled_features.empty());
+  EXPECT_FALSE(DoesComponentExtensionExist(
+      extension_misc::kAccessibilityCommonExtensionId));
+
+  // Not an accessibility common feature.
+  content::WindowedNotificationObserver spoken_feedback_extension_load_waiter(
+      extensions::NOTIFICATION_EXTENSION_HOST_DID_STOP_FIRST_LOAD,
+      content::NotificationService::AllSources());
+  pref_service->SetBoolean(ash::prefs::kAccessibilitySpokenFeedbackEnabled,
+                           true);
+  spoken_feedback_extension_load_waiter.Wait();
+  EXPECT_TRUE(enabled_features.empty());
+  EXPECT_FALSE(DoesComponentExtensionExist(
+      extension_misc::kAccessibilityCommonExtensionId));
+  EXPECT_TRUE(
+      DoesComponentExtensionExist(extension_misc::kChromeVoxExtensionId));
+}
+
+}  // namespace chromeos

chrome/browser/chromeos/accessibility/accessibility_extension_loader.cc

@@ -38,8 +38,9 @@ void AccessibilityExtensionLoader::SetProfile(
   if (!loaded_)
     return;
 
-  // If the extension was loaded on the previous profile, unload it there.
-  if (prev_profile)
+  // If the extension was loaded on the previous profile (which isn't the
+  // current profile), unload it there.
+  if (prev_profile && prev_profile != profile)
     UnloadExtensionFromProfile(prev_profile);
 
   // If the extension was already enabled, but not for this profile, add it

chrome/browser/chromeos/accessibility/accessibility_manager.cc

@@ -630,22 +630,23 @@ bool AccessibilityManager::IsAutoclickEnabled() const {
                          ash::prefs::kAccessibilityAutoclickEnabled);
 }
 
-void AccessibilityManager::OnAutoclickChanged() {
+void AccessibilityManager::OnAccessibilityCommonChanged(
+    const std::string& pref_name) {
   if (!profile_)
     return;
 
-  const bool enabled = profile_->GetPrefs()->GetBoolean(
-      ash::prefs::kAccessibilityAutoclickEnabled);
-
-  if (enabled)
+  const bool enabled = profile_->GetPrefs()->GetBoolean(pref_name);
+  if (enabled) {
     accessibility_common_extension_loader_->SetProfile(
         profile_, base::Closure() /* done_callback */);
+  }
 
-  if (autoclick_enabled_ == enabled)
+  size_t pref_count = accessibility_common_enabled_features_.count(pref_name);
+  if ((pref_count != 0 && enabled) || (pref_count == 0 && !enabled))
     return;
 
-  autoclick_enabled_ = enabled;
   if (enabled) {
+    accessibility_common_enabled_features_.insert(pref_name);
     if (!accessibility_common_extension_loader_->loaded()) {
       accessibility_common_extension_loader_->Load(
           profile_, base::BindRepeating(
@@ -656,7 +657,11 @@ void AccessibilityManager::OnAutoclickChanged() {
       PostLoadAccessibilityCommon();
     }
   } else {
-    accessibility_common_extension_loader_->Unload();
+    accessibility_common_enabled_features_.erase(pref_name);
+
+    if (accessibility_common_enabled_features_.empty()) {
+      accessibility_common_extension_loader_->Unload();
+    }
   }
 }
 
@@ -1030,6 +1035,11 @@ void AccessibilityManager::SetProfile(Profile* profile) {
   // Clear all dictation state on profile change.
   dictation_.reset();
 
+  // All features supported by accessibility common.
+  static const char* kAccessibilityCommonFeatures[] = {
+      ash::prefs::kAccessibilityAutoclickEnabled,
+      ash::prefs::kAccessibilityScreenMagnifierEnabled};
+
   if (profile) {
     // TODO(yoshiki): Move following code to PrefHandler.
     pref_change_registrar_.reset(new PrefChangeRegistrar);
@@ -1086,10 +1096,13 @@ void AccessibilityManager::SetProfile(Profile* profile) {
         ash::prefs::kAccessibilitySwitchAccessEnabled,
         base::BindRepeating(&AccessibilityManager::OnSwitchAccessChanged,
                             base::Unretained(this)));
-    pref_change_registrar_->Add(
-        ash::prefs::kAccessibilityAutoclickEnabled,
-        base::BindRepeating(&AccessibilityManager::OnAutoclickChanged,
-                            base::Unretained(this)));
+
+    for (const std::string& feature : kAccessibilityCommonFeatures) {
+      pref_change_registrar_->Add(
+          feature, base::BindRepeating(
+                       &AccessibilityManager::OnAccessibilityCommonChanged,
+                       base::Unretained(this)));
+    }
 
     local_state_pref_change_registrar_.reset(new PrefChangeRegistrar);
     local_state_pref_change_registrar_->Init(g_browser_process->local_state());
@@ -1127,7 +1140,9 @@ void AccessibilityManager::SetProfile(Profile* profile) {
   OnSpokenFeedbackChanged();
   OnSwitchAccessChanged();
   OnSelectToSpeakChanged();
-  OnAutoclickChanged();
+
+  for (const std::string& feature : kAccessibilityCommonFeatures)
+    OnAccessibilityCommonChanged(feature);
 }
 
 void AccessibilityManager::SetProfileByUser(const user_manager::User* user) {

chrome/browser/chromeos/accessibility/accessibility_manager.h

@@ -350,6 +350,10 @@ class AccessibilityManager
       base::RepeatingCallback<void(const gfx::Rect&)> observer);
   void SetSwitchAccessKeysForTest(const std::vector<int>& keys);
 
+  const std::set<std::string>& GetAccessibilityCommonEnabledFeaturesForTest() {
+    return accessibility_common_enabled_features_;
+  }
+
  protected:
   AccessibilityManager();
   ~AccessibilityManager() override;
@@ -380,7 +384,7 @@ class AccessibilityManager
   void OnFocusHighlightChanged();
   void OnTapDraggingChanged();
   void OnSelectToSpeakChanged();
-  void OnAutoclickChanged();
+  void OnAccessibilityCommonChanged(const std::string& pref_name);
   void OnSwitchAccessChanged();
 
   void CheckBrailleState();
@@ -438,7 +442,10 @@ class AccessibilityManager
   bool spoken_feedback_enabled_ = false;
   bool select_to_speak_enabled_ = false;
   bool switch_access_enabled_ = false;
-  bool autoclick_enabled_ = false;
+
+  // A set of pref names of enabled accessibility features using the
+  // accessibility common extension.
+  std::set<std::string> accessibility_common_enabled_features_;
 
   AccessibilityStatusCallbackList callback_list_;
 

chrome/browser/resources/chromeos/accessibility/BUILD.gn

@@ -70,7 +70,7 @@ manifest("accessibility_common_manifest") {
 manifest("accessibility_common_guest_manifest") {
   input_file = "accessibility_common_manifest.json.jinja2"
   output_file =
-      "$accessibility_out_dir/accessibility_common_guest_manifest.json"
+      "$accessibility_out_dir/accessibility_common_manifest_guest.json"
   key = "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"
   is_guest_manifest = true
 }

chrome/browser/resources/chromeos/accessibility/accessibility_common/BUILD.gn

@@ -25,6 +25,7 @@ run_jsbundler("accessibility_common_copied_files") {
   sources = [
     "accessibility_common_loader.js",
     "autoclick/autoclick.js",
+    "magnifier/magnifier.js",
   ]
   rewrite_rules = [
     rebase_path(".", root_build_dir) + ":",
@@ -80,7 +81,10 @@ js_type_check("closure_compile") {
 
 js_library("accessibility_common") {
   sources = [ "accessibility_common_loader.js" ]
-  deps = [ ":autoclick" ]
+  deps = [
+    ":autoclick",
+    ":magnifier",
+  ]
   externs_list = [
     "$externs_path/chrome_extensions.js",
     "$externs_path/accessibility_private.js",
@@ -95,3 +99,7 @@ js_library("autoclick") {
     "$externs_path/automation.js",
   ]
 }
+
+js_library("magnifier") {
+  sources = [ "magnifier/magnifier.js" ]
+}

chrome/browser/resources/chromeos/accessibility/accessibility_common/accessibility_common_loader.js

@@ -8,10 +8,10 @@
  */
 class AccessibilityCommon {
   constructor() {
-    /**
-     * @private {Autoclick}
-     */
+    /** @private {Autoclick} */
     this.autoclick_ = null;
+    /** @private {Magnifier} */
+    this.magnifier_ = null;
 
     this.init_();
   }
@@ -32,6 +32,11 @@ class AccessibilityCommon {
         {}, this.onAutoclickUpdated_.bind(this));
     chrome.accessibilityFeatures.autoclick.onChange.addListener(
         this.onAutoclickUpdated_.bind(this));
+
+    chrome.accessibilityFeatures.screenMagnifier.get(
+        {}, this.onMagnifierUpdated_.bind(this));
+    chrome.accessibilityFeatures.screenMagnifier.onChange.addListener(
+        this.onMagnifierUpdated_.bind(this));
   }
 
   /**
@@ -50,6 +55,18 @@ class AccessibilityCommon {
       this.autoclick_ = null;
     }
   }
+
+  /**
+   * @param {*} details
+   * @private
+   */
+  onMagnifierUpdated_(details) {
+    if (details.value && !this.magnifier_) {
+      this.magnifier_ = new Magnifier();
+    } else if (!details.value && this.magnifier_) {
+      this.magnifier_ = null;
+    }
+  }
 }
 
 // Initialize the AccessibilityCommon extension.

chrome/browser/resources/chromeos/accessibility/accessibility_common/magnifier/magnifier.js

+// Copyright 2020 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.
+
+/**
+ * Main class for the Chrome OS magnifier.
+ */
+class Magnifier {
+  constructor() {}
+}

chrome/browser/resources/chromeos/accessibility/accessibility_common_manifest.json.jinja2

@@ -12,6 +12,7 @@
   "background": {
     "scripts": [
       "accessibility_common/autoclick/autoclick.js",
+      "accessibility_common/magnifier/magnifier.js",
       "accessibility_common/accessibility_common_loader.js"
     ]
   },

chrome/test/BUILD.gn

@@ -2148,6 +2148,7 @@ if (!is_android) {
       sources += [
         "../browser/apps/platform_apps/app_window_interactive_uitest_base.cc",
         "../browser/apps/platform_apps/app_window_interactive_uitest_base.h",
+        "../browser/chromeos/accessibility/accessibility_common_browsertest.cc",
         "../browser/chromeos/accessibility/accessibility_manager_browsertest.cc",
         "../browser/chromeos/accessibility/dictation_chromeos_browsertest.cc",
         "../browser/chromeos/accessibility/magnification_controller_browsertest.cc",