Cleanup: Remove some std::map::operator[] usage in ApiResourceManager.

Also remove an unused header and add it where actually used.

Review URL: https://codereview.chromium.org/587453005

Cr-Commit-Position: refs/heads/master@{#295789}

extensions/browser/api/api_resource_manager.h

@@ -8,7 +8,6 @@
 #include <map>
 
 #include "base/containers/hash_tables.h"
-#include "base/lazy_instance.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/ref_counted.h"
 #include "base/scoped_observer.h"
@@ -230,12 +229,13 @@ class ApiResourceManager : public BrowserContextKeyedAPI,
         api_resource_map_[id] = resource_ptr;
 
         const std::string& extension_id = api_resource->owner_extension_id();
-        if (extension_resource_map_.find(extension_id) ==
-            extension_resource_map_.end()) {
-          extension_resource_map_[extension_id] = base::hash_set<int>();
+        ExtensionToResourceMap::iterator it =
+            extension_resource_map_.find(extension_id);
+        if (it == extension_resource_map_.end()) {
+          it = extension_resource_map_.insert(
+              std::make_pair(extension_id, base::hash_set<int>())).first;
         }
-        extension_resource_map_[extension_id].insert(id);
-
+        it->second.insert(id);
         return id;
       }
       return 0;
@@ -243,10 +243,10 @@ class ApiResourceManager : public BrowserContextKeyedAPI,
 
     void Remove(const std::string& extension_id, int api_resource_id) {
       DCHECK(ThreadingTraits::IsCalledOnValidThread());
-      if (GetOwnedResource(extension_id, api_resource_id) != NULL) {
-        DCHECK(extension_resource_map_.find(extension_id) !=
-               extension_resource_map_.end());
-        extension_resource_map_[extension_id].erase(api_resource_id);
+      if (GetOwnedResource(extension_id, api_resource_id)) {
+        ExtensionToResourceMap::iterator it =
+            extension_resource_map_.find(extension_id);
+        it->second.erase(api_resource_id);
         api_resource_map_.erase(api_resource_id);
       }
     }
@@ -325,11 +325,11 @@ class ApiResourceManager : public BrowserContextKeyedAPI,
 
     base::hash_set<int>* GetOwnedResourceIds(const std::string& extension_id) {
       DCHECK(ThreadingTraits::IsCalledOnValidThread());
-      if (extension_resource_map_.find(extension_id) ==
-          extension_resource_map_.end())
+      ExtensionToResourceMap::iterator it =
+          extension_resource_map_.find(extension_id);
+      if (it == extension_resource_map_.end())
         return NULL;
-
-      return &extension_resource_map_[extension_id];
+      return &(it->second);
     }
 
     void CleanupResourcesFromUnloadedExtension(
@@ -346,14 +346,14 @@ class ApiResourceManager : public BrowserContextKeyedAPI,
                                        bool remove_all) {
       DCHECK(ThreadingTraits::IsCalledOnValidThread());
 
-      if (extension_resource_map_.find(extension_id) ==
-          extension_resource_map_.end()) {
+      ExtensionToResourceMap::iterator it =
+          extension_resource_map_.find(extension_id);
+      if (it == extension_resource_map_.end())
         return;
-      }
 
       // Remove all resources, or the non persistent ones only if |remove_all|
       // is false.
-      base::hash_set<int>& resource_ids = extension_resource_map_[extension_id];
+      base::hash_set<int>& resource_ids = it->second;
       for (base::hash_set<int>::iterator it = resource_ids.begin();
            it != resource_ids.end();) {
         bool erase = false;

extensions/browser/api/bluetooth_low_energy/bluetooth_low_energy_connection.cc

@@ -4,6 +4,8 @@
 
 #include "extensions/browser/api/bluetooth_low_energy/bluetooth_low_energy_connection.h"
 
+#include "base/lazy_instance.h"
+
 namespace extensions {
 
 static base::LazyInstance<BrowserContextKeyedAPIFactory<

extensions/browser/api/bluetooth_low_energy/bluetooth_low_energy_notify_session.cc

@@ -4,6 +4,8 @@
 
 #include "extensions/browser/api/bluetooth_low_energy/bluetooth_low_energy_notify_session.h"
 
+#include "base/lazy_instance.h"
+
 namespace extensions {
 
 static base::LazyInstance<BrowserContextKeyedAPIFactory<

extensions/browser/api/bluetooth_socket/bluetooth_api_socket.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/bluetooth_socket/bluetooth_api_socket.h"
 
+#include "base/lazy_instance.h"
 #include "device/bluetooth/bluetooth_socket.h"
 #include "net/base/io_buffer.h"
 

extensions/browser/api/bluetooth_socket/bluetooth_socket_event_dispatcher.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/bluetooth_socket/bluetooth_socket_event_dispatcher.h"
 
+#include "base/lazy_instance.h"
 #include "device/bluetooth/bluetooth_device.h"
 #include "device/bluetooth/bluetooth_socket.h"
 #include "extensions/browser/api/bluetooth_socket/bluetooth_api_socket.h"

extensions/browser/api/cast_channel/cast_channel_api.cc

@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/json/json_writer.h"
+#include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/time/default_tick_clock.h"

extensions/browser/api/serial/serial_event_dispatcher.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/serial/serial_event_dispatcher.h"
 
+#include "base/lazy_instance.h"
 #include "extensions/browser/api/serial/serial_connection.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extensions_browser_client.h"

extensions/browser/api/socket/tcp_socket.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/socket/tcp_socket.h"
 
+#include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "extensions/browser/api/api_resource.h"

extensions/browser/api/socket/udp_socket.cc

@@ -6,6 +6,7 @@
 
 #include <algorithm>
 
+#include "base/lazy_instance.h"
 #include "extensions/browser/api/api_resource.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"

extensions/browser/api/sockets_tcp/tcp_socket_event_dispatcher.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/sockets_tcp/tcp_socket_event_dispatcher.h"
 
+#include "base/lazy_instance.h"
 #include "extensions/browser/api/socket/tcp_socket.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extension_system.h"

extensions/browser/api/sockets_tcp_server/tcp_server_socket_event_dispatcher.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/sockets_tcp_server/tcp_server_socket_event_dispatcher.h"
 
+#include "base/lazy_instance.h"
 #include "extensions/browser/api/socket/tcp_socket.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extensions_browser_client.h"

extensions/browser/api/sockets_udp/udp_socket_event_dispatcher.cc

@@ -4,6 +4,7 @@
 
 #include "extensions/browser/api/sockets_udp/udp_socket_event_dispatcher.h"
 
+#include "base/lazy_instance.h"
 #include "extensions/browser/api/socket/udp_socket.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extensions_browser_client.h"

extensions/browser/api/usb/usb_device_resource.cc

@@ -9,6 +9,7 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/lazy_instance.h"
 #include "base/synchronization/lock.h"
 #include "content/public/browser/browser_thread.h"
 #include "device/usb/usb_device_handle.h"