[iOS][Tail Suggest] Add formatter properties for tail suggest.

Exposes necessary tail suggest fields of an autocomplete match, wrapped
in Foundation types.

Bug: none
Change-Id: Ia8a8a1e69befc3a8e510dfa196deda1544b9290e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2571876
Commit-Queue: edchin <edchin@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Reviewed-by: Robbie Gibson <rkgibson@google.com>
Auto-Submit: Stepan Khapugin <stkhapugin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833799}

ios/chrome/browser/ui/omnibox/popup/autocomplete_match_formatter.mm

@@ -246,6 +246,19 @@ UIColor* DimColorIncognito() {
   return _match.has_tab_match;
 }
 
+#pragma mark tail suggest
+
+- (BOOL)isTailSuggestion {
+  return _match.type == AutocompleteMatchType::SEARCH_SUGGEST_TAIL;
+}
+
+- (NSString*)commonPrefix {
+  if (![self isTailSuggestion]) {
+    return @"";
+  }
+  return base::SysUTF16ToNSString(_match.tail_suggest_common_prefix);
+}
+
 #pragma mark helpers
 
 // Create a string to display for an entire answer line.

ios/chrome/browser/ui/omnibox/popup/autocomplete_suggestion.h

@@ -45,6 +45,15 @@ class GURL;
 
 - (id<OmniboxIcon>)icon;
 
+#pragma mark tail suggest
+
+// Yes if this is a tail suggestion. Used by the popup to display according to
+// tail suggest standards.
+- (BOOL)isTailSuggestion;
+
+// Common prefix for tail suggestions. Empty otherwise.
+- (NSString*)commonPrefix;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_OMNIBOX_POPUP_AUTOCOMPLETE_SUGGESTION_H_

ios/chrome/browser/ui/omnibox/popup/omnibox_popup_row_cell_unittest.mm

@@ -29,7 +29,8 @@
 @property(nonatomic, assign) GURL imageURL;
 @property(nonatomic, assign) GURL faviconPageURL;
 @property(nonatomic, strong) id<OmniboxIcon> icon;
-
+@property(nonatomic, assign) BOOL isTailSuggestion;
+@property(nonatomic, assign) NSString* commonPrefix;
 @end
 
 @implementation FakeAutocompleteMatch

ios/showcase/omnibox_popup/fake_autocomplete_suggestion.h

@@ -23,8 +23,9 @@
 @property(nonatomic) NSAttributedString* detailText;
 @property(nonatomic) NSInteger numberOfLines;
 @property(nonatomic) UIImage* suggestionTypeIcon;
-
 @property(nonatomic) id<OmniboxIcon> icon;
+@property(nonatomic, assign) BOOL isTailSuggestion;
+@property(nonatomic, copy) NSString* commonPrefix;
 
 // Simple suggestion with text.
 + (instancetype)simpleSuggestion;