[Offline pages] Fixing restoring bookmarks filter, when offline pages disabled

Ensures that when enhanced bookmarks UI is restoring the past filter
for content saved offline, and offline pages are disabled, it is treating
the state as invalid and reverts to the all bookmarks state.

BUG=581976

Review URL: https://codereview.chromium.org/1656103002

Cr-Commit-Position: refs/heads/master@{#372983}
(cherry picked from commit d1b363e)

Review URL: https://codereview.chromium.org/1662563002 .

Cr-Commit-Position: refs/branch-heads/2623@{#241}
Cr-Branched-From: 92d7753-refs/heads/master@{#369907}

Author: fgorski

chrome/android/java/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkUIState.java

@@ -8,6 +8,7 @@
 import android.text.TextUtils;
 
 import org.chromium.chrome.browser.UrlConstants;
+import org.chromium.chrome.browser.offlinepages.OfflinePageBridge;
 import org.chromium.components.bookmarks.BookmarkId;
 
 /**
@@ -151,8 +152,13 @@ boolean isValid(EnhancedBookmarksModel bookmarkModel) {
                     && !mFolder.equals(bookmarkModel.getRootFolderId());
         }
 
-        if (mState == STATE_FILTER && mFilter == null) return false;
+        if (mState == STATE_FILTER) {
+            if (mFilter == null) return false;
+            if (mFilter == EnhancedBookmarkFilter.OFFLINE_PAGES) {
+                return OfflinePageBridge.isEnabled();
+            }
+        }
 
         return true;
     }
-}
+}

chrome/android/javatests/src/org/chromium/chrome/browser/enhancedbookmarks/EnhancedBookmarkTest.java

@@ -241,4 +241,12 @@ public void testOpenBookmarkManagerInOfflinePageNoPersist() throws InterruptedEx
         assertEquals(UrlConstants.BOOKMARKS_URL,
                 EnhancedBookmarkUtils.getLastUsedUrl(getActivity()));
     }
+
+    @SmallTest
+    @CommandLineFlags.Add(ChromeSwitches.DISABLE_OFFLINE_PAGES)
+    public void testOpenBookmarkManagerInOfflinePageWhenDisabled() throws InterruptedException {
+        openBookmarkManager("chrome-native://bookmarks/filter/OFFLINE_PAGES");
+        EnhancedBookmarkDelegate delegate = mItemsContainer.getDelegateForTesting();
+        assertEquals(EnhancedBookmarkUIState.STATE_ALL_BOOKMARKS, delegate.getCurrentState());
+    }
 }