Make SettingsLauncher non-singleton

This is a first step towards modularizing SettingsLauncher.

See go/clank-modularize-settings-launcher for full details.

Bug: 1054193
Change-Id: Ib073e60aacce51ff7948621fc35c3bf2d6d68988
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2149885Reviewed-by: Matthew Jones <mdjones@chromium.org>
Reviewed-by: Pavel Yatsuk <pavely@chromium.org>
Commit-Queue: Natalie Chouinard <chouinard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#759879}

chrome/android/java/src/org/chromium/chrome/browser/settings/SettingsLauncher.java

@@ -8,33 +8,24 @@ import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
-
 import androidx.annotation.Nullable;
-import androidx.annotation.VisibleForTesting;
 import androidx.fragment.app.Fragment;
-
 import org.chromium.base.IntentUtils;
 
 /**
  * A utility class for launching Chrome Settings.
  */
 public class SettingsLauncher {
-    private static SettingsLauncher sSettingsLauncher = new SettingsLauncher();
-    private static SettingsLauncher sInstanceForTests;
-
-    @VisibleForTesting
-    protected SettingsLauncher() {}
+    public SettingsLauncher() {}
 
     /**
-     * Returns the singleton instance of this class.
+     * @return An instance of this class.
+     * @deprecated New code should construct {@link SettingsLauncher} directly.
      */
+    // TODO(crbug.com/1054193): Inline and remove this method.
+    @Deprecated
     public static SettingsLauncher getInstance() {
-        return sInstanceForTests == null ? sSettingsLauncher : sInstanceForTests;
-    }
-
-    @VisibleForTesting
-    public void setInstanceForTests(SettingsLauncher getter) {
-        sInstanceForTests = getter;
+        return new SettingsLauncher();
     }
 
     /**

chrome/android/java/src/org/chromium/chrome/browser/toolbar/HomeButton.java

@@ -66,6 +66,8 @@ public class HomeButton extends ChromeImageButton
     private static boolean sSaveContextMenuForTests;
     private ContextMenu mMenuForTests;
 
+    private SettingsLauncher mSettingsLauncher;
+
     public HomeButton(Context context, AttributeSet attrs) {
         super(context, attrs);
 
@@ -85,6 +87,8 @@ public class HomeButton extends ChromeImageButton
                 }
             }
         };
+
+        mSettingsLauncher = new SettingsLauncher();
     }
 
     public void destroy() {
@@ -143,7 +147,7 @@ public class HomeButton extends ChromeImageButton
         assert !isManagedByPolicy();
         if (isHomepageSettingsUIConversionEnabled()) {
             assert item.getItemId() == ID_SETTINGS;
-            SettingsLauncher.getInstance().launchSettingsPage(getContext(), HomepageSettings.class);
+            mSettingsLauncher.launchSettingsPage(getContext(), HomepageSettings.class);
         } else {
             assert item.getItemId() == ID_REMOVE;
             HomepageManager.getInstance().setPrefHomepageEnabled(false);
@@ -255,4 +259,9 @@ public class HomeButton extends ChromeImageButton
     public ContextMenu getMenuForTests() {
         return mMenuForTests;
     }
+
+    @VisibleForTesting
+    public void setSettingsLauncherForTests(SettingsLauncher settingsLauncher) {
+        mSettingsLauncher = settingsLauncher;
+    }
 }

chrome/android/javatests/src/org/chromium/chrome/browser/toolbar/HomeButtonTest.java

@@ -71,7 +71,6 @@ public class HomeButtonTest extends DummyUiActivityTestCase {
         super.setUpTest();
 
         MockitoAnnotations.initMocks(this);
-        SettingsLauncher.getInstance().setInstanceForTests(mSettingsLauncher);
 
         // Set the default test status for homepage button tests.
         // By default, the homepage is <b>enabled</b> and with customized URL.
@@ -84,6 +83,7 @@ public class HomeButtonTest extends DummyUiActivityTestCase {
             mIdHomeButton = View.generateViewId();
             mHomeButton = new HomeButton(getActivity(), null);
             mHomeButton.setId(mIdHomeButton);
+            mHomeButton.setSettingsLauncherForTests(mSettingsLauncher);
             HomeButton.setSaveContextMenuForTests(true);
 
             content.addView(mHomeButton);