Show Floating Toolbar when tapping a selectable TextLink in TextView.

Test: bit FrameworksCoreTests:android.widget.TextViewActivityTest\#testToolbarAppearsAfterLinkClicked
Bug: b/67629726
Change-Id: Ied7a1903a308db37d0eb288c8e611da8229f381a
diff --git a/core/java/android/view/textclassifier/TextLinks.java b/core/java/android/view/textclassifier/TextLinks.java
index 0e039e3..4fe5662 100644
--- a/core/java/android/view/textclassifier/TextLinks.java
+++ b/core/java/android/view/textclassifier/TextLinks.java
@@ -22,6 +22,8 @@
 import android.os.LocaleList;
 import android.text.SpannableString;
 import android.text.style.ClickableSpan;
+import android.view.View;
+import android.widget.TextView;
 
 import com.android.internal.util.Preconditions;
 
@@ -189,9 +191,14 @@
      * @hide
      */
     public static final Function<TextLink, ClickableSpan> DEFAULT_SPAN_FACTORY =
-            textLink -> {
-                // TODO: Implement.
-                throw new UnsupportedOperationException("Not yet implemented");
+            textLink -> new ClickableSpan() {
+                @Override
+                public void onClick(View widget) {
+                    if (widget instanceof TextView) {
+                        final TextView textView = (TextView) widget;
+                        textView.requestActionMode(textLink);
+                    }
+                }
             };
 
     /**