Reporting API: Remove Persister.

We've decided to persist using SQLite, so there's no periodic "persist
everything" task that needs to happen, so the ReportingPersister no
longer needs to exist.

Bug: 
Change-Id: If229bc8cc5b946385c1f2934021b553cc5ae48fc
Reviewed-on: https://chromium-review.googlesource.com/797852
Commit-Queue: Julia Tuttle <juliatuttle@chromium.org>
Reviewed-by: Matt Menke <mmenke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521356}

net/BUILD.gn

@@ -1833,8 +1833,6 @@ component("net") {
         "reporting/reporting_network_change_observer.h",
         "reporting/reporting_observer.cc",
         "reporting/reporting_observer.h",
-        "reporting/reporting_persister.cc",
-        "reporting/reporting_persister.h",
         "reporting/reporting_policy.cc",
         "reporting/reporting_policy.h",
         "reporting/reporting_report.cc",
@@ -5372,7 +5370,6 @@ test("net_unittests") {
       "reporting/reporting_garbage_collector_unittest.cc",
       "reporting/reporting_header_parser_unittest.cc",
       "reporting/reporting_network_change_observer_unittest.cc",
-      "reporting/reporting_persister_unittest.cc",
       "reporting/reporting_service_unittest.cc",
       "reporting/reporting_test_util.cc",
       "reporting/reporting_test_util.h",

net/reporting/reporting_context.cc

@@ -20,7 +20,6 @@
 #include "net/reporting/reporting_garbage_collector.h"
 #include "net/reporting/reporting_network_change_observer.h"
 #include "net/reporting/reporting_observer.h"
-#include "net/reporting/reporting_persister.h"
 #include "net/reporting/reporting_policy.h"
 #include "net/reporting/reporting_uploader.h"
 
@@ -80,7 +79,6 @@ ReportingContext::ReportingContext(const ReportingPolicy& policy,
       cache_(ReportingCache::Create(this)),
       endpoint_manager_(ReportingEndpointManager::Create(this)),
       delivery_agent_(ReportingDeliveryAgent::Create(this)),
-      persister_(ReportingPersister::Create(this)),
       garbage_collector_(ReportingGarbageCollector::Create(this)),
       network_change_observer_(ReportingNetworkChangeObserver::Create(this)) {}
 

net/reporting/reporting_context.h

@@ -27,7 +27,6 @@ class ReportingEndpointManager;
 class ReportingGarbageCollector;
 class ReportingNetworkChangeObserver;
 class ReportingObserver;
-class ReportingPersister;
 class ReportingUploader;
 class URLRequestContext;
 
@@ -57,8 +56,6 @@ class NET_EXPORT ReportingContext {
     return garbage_collector_.get();
   }
 
-  ReportingPersister* persister() { return persister_.get(); }
-
   void AddObserver(ReportingObserver* observer);
   void RemoveObserver(ReportingObserver* observer);
 
@@ -91,9 +88,6 @@ class NET_EXPORT ReportingContext {
   // |cache_|, and |endpoint_manager_|.
   std::unique_ptr<ReportingDeliveryAgent> delivery_agent_;
 
-  // |persister_| must come after |clock_|, |tick_clock_|, and |cache_|.
-  std::unique_ptr<ReportingPersister> persister_;
-
   // |garbage_collector_| must come after |tick_clock_| and |cache_|.
   std::unique_ptr<ReportingGarbageCollector> garbage_collector_;