Mirror syncfs log to console and WebUI, with LogSeverity support.

chrome/browser/sync_file_system/logger.cc

Index: chrome/browser/sync_file_system/logger.cc
diff --git a/chrome/browser/sync_file_system/logger.cc b/chrome/browser/sync_file_system/logger.cc
index 55705c95b16666dccbe2c553a4e7d027887471a5..43b18c6b156f0e193a5e0e4b04b9fd39e5c062ae 100644
--- a/chrome/browser/sync_file_system/logger.cc
+++ b/chrome/browser/sync_file_system/logger.cc
@@ -4,7 +4,9 @@
 
 #include "chrome/browser/sync_file_system/logger.h"
 
+#include "base/file_util.h"
 #include "base/lazy_instance.h"
+#include "base/location.h"
 #include "base/stringprintf.h"
 #include "chrome/browser/google_apis/event_logger.h"
 
@@ -15,9 +17,34 @@ namespace {
 static base::LazyInstance<google_apis::EventLogger> g_logger =
     LAZY_INSTANCE_INITIALIZER;
 
+std::string LogSeverityToString(logging::LogSeverity level) {
+  switch (level) {
+    case logging::LOG_ERROR:
+      return "ERROR";
+    case logging::LOG_WARNING:
+      return "WARNING";
+    case logging::LOG_INFO:
+      return "INFO";
+  }
+
+  NOTREACHED();
+  return "Unknown Log Severity";
+}
+
 }  // namespace
 
-void Log(const char* format, ...) {
+void ClearLog() {
+  g_logger.Pointer()->SetHistorySize(google_apis::kDefaultHistorySize);
+}
+
+void Log(logging::LogSeverity severity,
+         const tracked_objects::Location& location,
+         const char* format,
+         ...) {
+  // Ignore log if level severity is not high enough.
+  if (severity < logging::GetMinLogLevel())
+    return;
+
   std::string what;
 
   va_list args;
@@ -25,10 +52,23 @@ void Log(const char* format, ...) {
   base::StringAppendV(&what, format, args);
   va_end(args);
 
+  // Use same output format as normal console logger.
+  base::FilePath path = base::FilePath::FromUTF8Unsafe(location.file_name());
+  std::string log_output = base::StringPrintf(
+      "[%s: %s(%d)] %s",
+      LogSeverityToString(severity).c_str(),
+      path.BaseName().AsUTF8Unsafe().c_str(),
+      location.line_number(),
+      what.c_str());
+
+  // Log to WebUI.
   // On thread-safety: LazyInstance guarantees thread-safety for the object
   // creation. EventLogger::Log() internally maintains the lock.
   google_apis::EventLogger* ptr = g_logger.Pointer();
-  ptr->Log("%s", what.c_str());
+  ptr->Log("%s", log_output.c_str());
+
+  // Log to console.
+  logging::RawLog(severity, log_output.c_str());
 }
 
 std::vector<google_apis::EventLogger::Event> GetLogHistory() {