[Extensions] Use LazyContextId in maps instead of std::pair.

We use std::pair as both a key and a value in some maps. Using LazyContextId makes the code more readable and a bit more efficient in some places.

Bug: 915814
Change-Id: I9026bff13d74e093b6d703b7d4d95d07fe33e3c6
Reviewed-on: https://chromium-review.googlesource.com/c/1384751
Commit-Queue: David Bertoni <[email protected]>
Reviewed-by: Istiaque Ahmed <[email protected]>
Cr-Commit-Position: refs/heads/master@{#618657}
diff --git a/extensions/browser/lazy_background_task_queue.cc b/extensions/browser/lazy_background_task_queue.cc
index 69f0db3..c0a5fe3 100644
--- a/extensions/browser/lazy_background_task_queue.cc
+++ b/extensions/browser/lazy_background_task_queue.cc
@@ -91,8 +91,7 @@
   const ExtensionId& extension_id = context_id.extension_id();
   content::BrowserContext* const browser_context = context_id.browser_context();
   PendingTasksList* tasks_list = nullptr;
-  PendingTasksKey key(browser_context, extension_id);
-  auto it = pending_tasks_.find(key);
+  auto it = pending_tasks_.find(context_id);
   if (it == pending_tasks_.end()) {
     const Extension* extension = ExtensionRegistry::Get(browser_context)
                                      ->enabled_extensions()
@@ -108,7 +107,7 @@
     }
     auto tasks_list_tmp = std::make_unique<PendingTasksList>();
     tasks_list = tasks_list_tmp.get();
-    pending_tasks_[key] = std::move(tasks_list_tmp);
+    pending_tasks_[context_id] = std::move(tasks_list_tmp);
   } else {
     tasks_list = it->second.get();
   }