[WebLayer] Make sure new tab is focused when created

This is similar logic to what AwContents.java uses when creating a
popup.

Bug: 1030186
Change-Id: I0f207dae5ec53c0df68adb504544ec769534ce01
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1947639Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#721261}

weblayer/browser/java/org/chromium/weblayer_private/ContentView.java

@@ -111,7 +111,16 @@ public class ContentView extends FrameLayout
     }
 
     public void setWebContents(WebContents webContents) {
+        boolean wasFocused = isFocused();
+        boolean wasWindowFocused = hasWindowFocus();
+        boolean wasAttached = isAttachedToWindow();
+        if (wasFocused) onFocusChanged(false, View.FOCUS_FORWARD, null);
+        if (wasWindowFocused) onWindowFocusChanged(false);
+        if (wasAttached) onDetachedFromWindow();
         mWebContents = webContents;
+        if (wasFocused) onFocusChanged(true, View.FOCUS_FORWARD, null);
+        if (wasWindowFocused) onWindowFocusChanged(true);
+        if (wasAttached) onAttachedToWindow();
     }
 
     @Override