Remove isVoiceSearchResultsTab from tab

This was created for voicesearch bar which is removed with the new UI.

Bug: 898697, 778416
Change-Id: Ice43ef892a886bf616f8bc2712c0a6b2d48b29f8
Reviewed-on: https://chromium-review.googlesource.com/c/1353936Reviewed-by: Eugene But <eugenebut@chromium.org>
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611914}

ios/chrome/browser/tabs/tab.h

@@ -91,9 +91,6 @@ extern NSString* const kProxyPassthroughHeaderValue;
 // Delegate used to show HTTP Authentication dialogs.
 @property(nonatomic, weak) id<TabDialogDelegate> dialogDelegate;
 
-// Whether this tab is displaying a voice search result.
-@property(nonatomic, readonly) BOOL isVoiceSearchResultsTab;
-
 // |YES| if the tab has finished loading.
 @property(nonatomic, readonly) BOOL loadFinished;
 

ios/chrome/browser/tabs/tab.mm

@@ -66,7 +66,6 @@
 #import "ios/chrome/browser/ui/open_in_controller.h"
 #import "ios/chrome/browser/ui/overscroll_actions/overscroll_actions_controller.h"
 #include "ios/chrome/browser/ui/util/ui_util.h"
-#import "ios/chrome/browser/voice/voice_search_navigations_tab_helper.h"
 #import "ios/chrome/browser/web/page_placeholder_tab_helper.h"
 #import "ios/chrome/browser/web/tab_id_tab_helper.h"
 #include "ios/chrome/grit/ios_strings.h"
@@ -237,23 +236,6 @@ NSString* const kTabUrlKey = @"url";
   overscrollActionsControllerDelegate_ = overscrollActionsControllerDelegate;
 }
 
-- (BOOL)isVoiceSearchResultsTab {
-  // TODO(crbug.com/778416): Move this logic entirely into helper.
-  // If nothing has been loaded in the Tab, it cannot be displaying a voice
-  // search results page.
-  web::NavigationItem* item =
-      self.webState->GetNavigationManager()->GetVisibleItem();
-  if (!item)
-    return NO;
-  // Navigating through history to a NavigationItem that was created for a voice
-  // search query should just be treated like a normal page load.
-  if ((item->GetTransitionType() & ui::PAGE_TRANSITION_FORWARD_BACK) != 0)
-    return NO;
-  // Check whether |item| has been marked as a voice search result navigation.
-  return VoiceSearchNavigationTabHelper::FromWebState(self.webState)
-      ->IsNavigationFromVoiceSearch(item);
-}
-
 - (BOOL)loadFinished {
   return self.webState && !self.webState->IsLoading();
 }