Make SDCH dictionaries persistent across browser restart.

chrome/browser/profiles/profile_impl_io_data.cc

Index: chrome/browser/profiles/profile_impl_io_data.cc
diff --git a/chrome/browser/profiles/profile_impl_io_data.cc b/chrome/browser/profiles/profile_impl_io_data.cc
index 5af118651a2aaa4c21d25a03237586d558a741d4..8cccd0f03cdd6daea468c38dcd9d1f9f18e02f2d 100644
--- a/chrome/browser/profiles/profile_impl_io_data.cc
+++ b/chrome/browser/profiles/profile_impl_io_data.cc
@@ -9,6 +9,8 @@
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/field_trial.h"
+#include "base/prefs/json_pref_store.h"
+#include "base/prefs/pref_filter.h"
 #include "base/prefs/pref_member.h"
 #include "base/prefs/pref_service.h"
 #include "base/profiler/scoped_tracker.h"
@@ -66,6 +68,9 @@
 
 namespace {
 
+// Seconds to delay writing persisted preferences to disk.
+const int kPrefsCommitDelay = 10;
+
 net::BackendType ChooseCacheBackendType() {
 #if defined(OS_ANDROID)
   return net::CACHE_BACKEND_SIMPLE;
@@ -402,9 +407,11 @@ ProfileImplIOData::LazyParams::~LazyParams() {}
 
 ProfileImplIOData::ProfileImplIOData()
     : ProfileIOData(Profile::REGULAR_PROFILE),
+      network_store_commit_timer_(false, false),
       http_server_properties_manager_(NULL),
       app_cache_max_size_(0),
-      app_media_cache_max_size_(0) {
+      app_media_cache_max_size_(0),
+      factory_(this) {
 }
 
 ProfileImplIOData::~ProfileImplIOData() {
@@ -424,6 +431,16 @@ void ProfileImplIOData::InitializeInternal(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(
           "436671 ProfileImplIOData::InitializeInternal"));
 
+  // Set up a persistent store for use by the network stack on the IO thread.
+  base::FilePath network_json_store_filepath(
+      profile_path_.Append(chrome::kNetworkPersistentStateFilename));
+  network_json_store_ = new JsonPrefStore(
+      network_json_store_filepath,
+      JsonPrefStore::GetTaskRunnerForFile(network_json_store_filepath,
+                                          BrowserThread::GetBlockingPool()),
+      scoped_ptr<PrefFilter>());
+  network_json_store_->ReadPrefsAsync(nullptr);
+
   net::URLRequestContext* main_context = main_request_context();
 
   IOThread* const io_thread = profile_params->io_thread;
@@ -611,6 +628,7 @@ void ProfileImplIOData::InitializeInternal(
   sdch_manager_.reset(new net::SdchManager);
   sdch_policy_.reset(new net::SdchOwner(sdch_manager_.get(), main_context));
   main_context->set_sdch_manager(sdch_manager_.get());
+  sdch_policy_->EnablePersistentStorage(network_json_store_.get());
 
   // Create a media request context based on the main context, but using a
   // media cache.  It shares the same job factory as the main context.
@@ -853,3 +871,20 @@ void ProfileImplIOData::ClearNetworkingHistorySinceOnIOThread(
   DCHECK(http_server_properties_manager_);
   http_server_properties_manager_->Clear(completion);
 }
+
+void ProfileImplIOData::FlushPrefsToDisk() {
+  network_json_store_->CommitPendingWrite();
+}
+
+void ProfileImplIOData::OnPrefValueChanged(const std::string& key) {
+  // Schedule a write to disk for the preferences.  This will
+  // reset (i.e. push out) any previously scheduled but untriggered
+  // timer.  In other words, if there's a lot of preference activity,
+  // disk commit will be delayed until kPrefsCommitDelay seconds
+  // after it stops.
+  network_store_commit_timer_.Start(
+      FROM_HERE, base::TimeDelta::FromSeconds(kPrefsCommitDelay),
+      base::Bind(&ProfileImplIOData::FlushPrefsToDisk, factory_.GetWeakPtr()));

[Bernhard Bauer, 2015/02/02 14:39:46]

JsonPrefStore has an internal timer that will commit pending writes (also every
ten seconds). The explicit method is only for cases where you want to commit
*now* (like right before shutdown).

In any case, using a weak pointer here is probably not necessary, as the timer
is a member, so it will cancel itself when this object is destroyed. 

[Randy Smith (Not in Mondays), 2015/02/04 19:29:03]

That makes my life simpler!  Much excess stuff removed.

+}
+
+void ProfileImplIOData::OnInitializationCompleted(bool succeeded) {}