Add API WebView.getWebViewLooper()

We want to rename WebView.getLooper() to contrast it better with the
unrelated method WebView.getHandler(). For now we just create a method
to replace WebView.getLooper(), so that we can remove references to
WebView.getLooper() before removing it.

Bug: 74831609
Test: make
Change-Id: I8e493a67aa078f9c8ceea6706dc940abacfdd6e6
diff --git a/api/current.txt b/api/current.txt
index f5990eb..9d2c568 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -51997,6 +51997,7 @@
     method public android.webkit.WebChromeClient getWebChromeClient();
     method public static java.lang.ClassLoader getWebViewClassLoader();
     method public android.webkit.WebViewClient getWebViewClient();
+    method public android.os.Looper getWebViewLooper();
     method public void goBack();
     method public void goBackOrForward(int);
     method public void goForward();
diff --git a/core/java/android/webkit/WebView.java b/core/java/android/webkit/WebView.java
index 5178a97..fc94b1f 100644
--- a/core/java/android/webkit/WebView.java
+++ b/core/java/android/webkit/WebView.java
@@ -2451,6 +2451,14 @@
      * Returns the {@link Looper} corresponding to the thread on which WebView calls must be made.
      */
     @NonNull
+    public Looper getWebViewLooper() {
+        return mWebViewThread;
+    }
+
+    /**
+     * Returns the {@link Looper} corresponding to the thread on which WebView calls must be made.
+     */
+    @NonNull
     public Looper getLooper() {
         return mWebViewThread;
     }