Added UMA for usage of BudgetAPI calls.

chrome/browser/budget_service/budget_manager.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_BUDGET_SERVICE_BUDGET_MANAGER_H_
 #define CHROME_BROWSER_BUDGET_SERVICE_BUDGET_MANAGER_H_
 
 #include <map>
 #include <memory>
 
@@ skipping 45 matching lines @@
 
   // Spend budget, first consuming a reservation if one exists, or spend
   // directly from the budget.
   void Consume(const url::Origin& origin,
                blink::mojom::BudgetOperationType type,
                const ConsumeCallback& callback);
 
  private:
   friend class BudgetManagerTest;
 
+  // Called as a callback from BudgetDatabase when it returns the GetBudget
+  // details.

[Peter Beverloo, 2016/11/28 10:59:00]

micro nit: I don't think these comments (dito re: the following two methods) add
any value at all. Up to you.

[harkness, 2016/11/28 13:58:04]

I agree in this case. I've removed this one and the other two.

+  void DidGetBudget(const GetBudgetCallback& callback,
+                    blink::mojom::BudgetServiceErrorType error,
+                    mojo::Array<blink::mojom::BudgetStatePtr> budget);
+
   // Called as a callback from BudgetDatabase after it made a SpendBudget
   // decision.
   void DidConsume(const ConsumeCallback& callback,
                   blink::mojom::BudgetServiceErrorType error,
                   bool success);
 
   // Called as a callback from BudgetDatabase after it has made a reserve
   // decision.
   void DidReserve(const url::Origin& origin,
                   const ReserveCallback& callback,
                   blink::mojom::BudgetServiceErrorType error,
                   bool success);
 
   Profile* profile_;
   BudgetDatabase db_;
 
   std::map<url::Origin, int> reservation_map_;
   base::WeakPtrFactory<BudgetManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BudgetManager);
 };
 
 #endif  // CHROME_BROWSER_BUDGET_SERVICE_BUDGET_MANAGER_H_