(2nd try) Add a helper class that keeps per-profile information for FileSystem API

chrome/browser/profile_impl.cc

Index: chrome/browser/profile_impl.cc
diff --git a/chrome/browser/profile_impl.cc b/chrome/browser/profile_impl.cc
index 650b956569cabd2921891939bc63ade4003b540a..0f8d99780f6e5b1a16d03fa6b4e30c3d64560e19 100644
--- a/chrome/browser/profile_impl.cc
+++ b/chrome/browser/profile_impl.cc
@@ -32,6 +32,7 @@
 #include "chrome/browser/extensions/extensions_service.h"
 #include "chrome/browser/extensions/user_script_master.h"
 #include "chrome/browser/favicon_service.h"
+#include "chrome/browser/file_system/file_system_host_context.h"
 #include "chrome/browser/find_bar_state.h"
 #include "chrome/browser/geolocation/geolocation_content_settings_map.h"
 #include "chrome/browser/geolocation/geolocation_permission_context.h"
@@ -979,6 +980,14 @@ PersonalDataManager* ProfileImpl::GetPersonalDataManager() {
   return personal_data_manager_.get();
 }
 
+FileSystemHostContext* ProfileImpl::GetFileSystemHostContext() {
+  if (!file_system_host_context_.get())
+    file_system_host_context_ = new FileSystemHostContext(
+        GetPath(), IsOffTheRecord());
+  DCHECK(file_system_host_context_.get());
+  return file_system_host_context_.get();
+}
+
 void ProfileImpl::InitThemes() {
   if (!created_theme_provider_) {
 #if defined(TOOLKIT_USES_GTK)