Move Singleton and related structs to namespace base

Public APIs from base should live inside base:: so moved Singleton class
and structs to base{} and fixed consumers.

also fixed:

** Presubmit ERRORS **
Found Singleton<T> in the following header files.
Please move them to an appropriate source file so that the template
gets instantiated in a single compilation unit.
  chrome/browser/plugins/plugin_finder.h \
  chromecast/media/base/media_message_loop.h \
  content/browser/media/android/media_drm_credential_manager.h

Presubmit warnings:
src/chrome/browser/extensions/warning_badge_service_factory.h:5:
  #ifndef header guard has wrong style, please use:
  CHROME_BROWSER_EXTENSIONS_WARNING_BADGE_SERVICE_FACTORY_H_
  [build/header_guard] [5]
src/chrome/browser/extensions/warning_badge_service_factory.h:39:
  #endif line should be "#endif  //
  CHROME_BROWSER_EXTENSIONS_WARNING_BADGE_SERVICE_FACTORY_H_"
  [build/header_guard] [5]

[email protected]

Review URL: https://codereview.chromium.org/1308823002

Cr-Commit-Position: refs/heads/master@{#348136}
diff --git a/base/logging_win.h b/base/logging_win.h
index aa48e22..de34a64 100644
--- a/base/logging_win.h
+++ b/base/logging_win.h
@@ -12,8 +12,10 @@
 #include "base/win/event_trace_provider.h"
 #include "base/logging.h"
 
+namespace base {
 template <typename Type>
 struct StaticMemorySingletonTraits;
+}  // namespace base
 
 namespace logging {
 
@@ -71,7 +73,7 @@
   // restored in OnEventsDisabled.
   logging::LogSeverity old_log_level_;
 
-  friend struct StaticMemorySingletonTraits<LogEventProvider>;
+  friend struct base::StaticMemorySingletonTraits<LogEventProvider>;
   DISALLOW_COPY_AND_ASSIGN(LogEventProvider);
 };