weblayer: Remove extra onShow/onHide

The code is also incorrect as it skips checking other states.

Bug: 1084500
Change-Id: I44ef55b2c47fca901e9c6f52e5cc07834aa858d6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2215405Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#771847}

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

@@ -328,7 +328,6 @@ public final class TabImpl extends ITab.Stub {
         TabImplJni.get().setBrowserControlsContainerViews(
                 mNativeTab, topControlsContainerViewHandle, bottomControlsContainerViewHandle);
         updateWebContentsVisibility();
-        mWebContents.onShow();
     }
 
     /**
@@ -336,7 +335,6 @@ public final class TabImpl extends ITab.Stub {
      */
     public void onDidLoseActive() {
         hideFindInPageUiAndNotifyClient();
-        mWebContents.onHide();
         updateWebContentsVisibility();
         TabImplJni.get().setBrowserControlsContainerViews(mNativeTab, 0, 0);
     }