Miscellaneous permissions cleanup.

This patch:
* Introduces a new method PermissionRequest::IsDuplicateOf, rather than
  relying on comparing the result of GetMessageTextFragment (which
  returns a human-readable string) to determine whether two requests are
  duplicates.
* Makes PermissionRequest::GetMessageTextFragment desktop-only, as it
  was only used elsewhere in the aforementioned duplicates logic.
* Uses std::u16string in MockPermissionRequest everywhere.
* And deletes a few bits of unused code.

Bug: 1110905
Change-Id: I39704d74d9456674a30c9483ed10423c84e998f6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2778492
Commit-Queue: Bret Sepulveda <[email protected]>
Reviewed-by: Xiaohan Wang <[email protected]>
Reviewed-by: Xing Liu <[email protected]>
Reviewed-by: Dana Fried <[email protected]>
Reviewed-by: Ben Wells <[email protected]>
Reviewed-by: Olesia Marukhno <[email protected]>
Reviewed-by: Kamila Hasanbega <[email protected]>
Reviewed-by: Ravjit Singh Uppal <[email protected]>
Cr-Commit-Position: refs/heads/master@{#874233}
diff --git a/components/permissions/permission_request.h b/components/permissions/permission_request.h
index 65523f9..54f0fb4b 100644
--- a/components/permissions/permission_request.h
+++ b/components/permissions/permission_request.h
@@ -33,31 +33,25 @@
   // The type of this request.
   virtual RequestType GetRequestType() const = 0;
 
+  // Whether |this| and |other_request| are duplicates and therefore don't both
+  // need to be shown in the UI.
+  virtual bool IsDuplicateOf(PermissionRequest* other_request) const;
+
 #if defined(OS_ANDROID)
   // Returns the full prompt text for this permission. This is currently only
   // used on Android.
   virtual std::u16string GetMessageText() const = 0;
-
-  // Returns the title of this permission as text when the permission request is
-  // displayed as a quiet prompt. Only used on Android. By default it returns
-  // the same value as |GetTitleText| unless overridden.
-  virtual std::u16string GetQuietTitleText() const;
-
-  // Returns the full prompt text for this permission as text when the
-  // permission request is displayed as a quiet prompt. Only used on Android. By
-  // default it returns the same value as |GetMessageText| unless overridden.
-  virtual std::u16string GetQuietMessageText() const;
 #endif
 
 #if !defined(OS_ANDROID)
   // Returns the short text for the chip button related to this permission.
   virtual base::Optional<std::u16string> GetChipText() const;
-#endif
 
   // Returns the shortened prompt text for this permission. The permission
   // bubble may coalesce different requests, and if it does, this text will
   // be displayed next to an image and indicate the user grants the permission.
   virtual std::u16string GetMessageTextFragment() const = 0;
+#endif
 
   // Get the origin on whose behalf this permission request is being made.
   virtual GURL GetOrigin() const = 0;