Remove didRemoveTab & didChangeActiveTab as TabModelObserver methods.

All their usages have been removed.

Bug: 911350
Change-Id: Iadf2b47bdb9166906d0d9f9c6298ab8d04e8963e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1621033Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#662151}

ios/chrome/browser/tabs/tab_model_observer.h

@@ -21,23 +21,12 @@
          atIndex:(NSUInteger)index
     inForeground:(BOOL)fg;
 
-// A tab was removed at the given index.
-- (void)tabModel:(TabModel*)model
-    didRemoveTab:(Tab*)tab
-         atIndex:(NSUInteger)index;
-
 // A Tab was replaced in the model, at the given index.
 - (void)tabModel:(TabModel*)model
     didReplaceTab:(Tab*)oldTab
           withTab:(Tab*)newTab
           atIndex:(NSUInteger)index;
 
-// A tab was activated.
-- (void)tabModel:(TabModel*)model
-    didChangeActiveTab:(Tab*)newTab
-           previousTab:(Tab*)previousTab
-               atIndex:(NSUInteger)index;
-
 // Some properties about the given tab changed, such as the URL or title.
 - (void)tabModel:(TabModel*)model didChangeTab:(Tab*)tab;
 

ios/chrome/browser/tabs/tab_model_observers_bridge.mm

@@ -56,34 +56,4 @@
                        atIndex:static_cast<NSUInteger>(atIndex)];
 }
 
-- (void)webStateList:(WebStateList*)webStateList
-    didDetachWebState:(web::WebState*)webState
-              atIndex:(int)atIndex {
-  DCHECK_GE(atIndex, 0);
-  [_tabModelObservers tabModel:_tabModel
-                  didRemoveTab:LegacyTabHelper::GetTabForWebState(webState)
-                       atIndex:static_cast<NSUInteger>(atIndex)];
-}
-
-- (void)webStateList:(WebStateList*)webStateList
-    didChangeActiveWebState:(web::WebState*)newWebState
-                oldWebState:(web::WebState*)oldWebState
-                    atIndex:(int)atIndex
-                     reason:(int)reason {
-  if (!newWebState)
-    return;
-
-  // If there is no new active WebState, then it means that the atIndex will be
-  // set to WebStateList::kInvalidIndex, so only check for a positive index if
-  // there is a new WebState.
-  DCHECK_GE(atIndex, 0);
-
-  Tab* oldTab =
-      oldWebState ? LegacyTabHelper::GetTabForWebState(oldWebState) : nil;
-  [_tabModelObservers tabModel:_tabModel
-            didChangeActiveTab:LegacyTabHelper::GetTabForWebState(newWebState)
-                   previousTab:oldTab
-                       atIndex:static_cast<NSUInteger>(atIndex)];
-}
-
 @end