🏠 Add expand button and flag to enable it

chrome/android/java/src/org/chromium/chrome/browser/util/FeatureUtilities.java

Index: chrome/android/java/src/org/chromium/chrome/browser/util/FeatureUtilities.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/util/FeatureUtilities.java b/chrome/android/java/src/org/chromium/chrome/browser/util/FeatureUtilities.java
index 8926478adf010faeb43b60a6cb5723137541a4c9..e1bb9e01e47190499cdabe63db3af3d39bb76b88 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/util/FeatureUtilities.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/util/FeatureUtilities.java
@@ -265,6 +265,13 @@ public class FeatureUtilities {
         return sChromeHomeEnabled;
     }
 
+    /**
+     * @return Whether or not the expand button for Chrome Home is enabled.
+     */
+    public static boolean isChromeHomeExpandButtonEnabled() {
+        return ChromeFeatureList.isEnabled(ChromeFeatureList.CHROME_HOME_EXPAND_BUTTON);
+    }
+
     private static native void nativeSetCustomTabVisible(boolean visible);
     private static native void nativeSetIsInMultiWindowMode(boolean isInMultiWindowMode);
 }