reland: weblayer: fixs enum conversions

These got lost in the rename.

BUG=none
TEST=none
TBR=jam@chromium.org

Change-Id: I0273dd26860950d0eb87215f84914d5c511205f6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1903758Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713563}

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

@@ -9,6 +9,7 @@ import android.os.RemoteException;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
 import org.chromium.base.annotations.NativeMethods;
+import org.chromium.weblayer_private.interfaces.NewTabType;
 
 /**
  * Owns the c++ NewTabCallback class, which is responsible for forwarding all
@@ -30,8 +31,24 @@ public final class NewTabCallbackProxy {
         mNativeNewTabCallbackProxy = 0;
     }
 
+    @NewTabType
+    private static int implTypeToJavaType(@ImplNewTabType int type) {
+        switch (type) {
+            case ImplNewTabType.FOREGROUND:
+                return NewTabType.FOREGROUND_TAB;
+            case ImplNewTabType.BACKGROUND:
+                return NewTabType.BACKGROUND_TAB;
+            case ImplNewTabType.NEW_POPUP:
+                return NewTabType.NEW_POPUP;
+            case ImplNewTabType.NEW_WINDOW:
+                return NewTabType.NEW_WINDOW;
+        }
+        assert false;
+        return NewTabType.FOREGROUND_TAB;
+    }
+
     @CalledByNative
-    public void onNewTab(long nativeTab, int mode) throws RemoteException {
+    public void onNewTab(long nativeTab, @ImplNewTabType int mode) throws RemoteException {
         // This class should only be created while the tab is attached to a fragment.
         assert mTab.getBrowser() != null;
         TabImpl tab =