Cleanup: Better constify some strings in chrome/browser/{chromeos,extensions}.

chrome/browser/extensions/api/downloads/downloads_api.cc

Index: chrome/browser/extensions/api/downloads/downloads_api.cc
diff --git a/chrome/browser/extensions/api/downloads/downloads_api.cc b/chrome/browser/extensions/api/downloads/downloads_api.cc
index 84e184241feb522b78641491b08839f0913d2ecc..4676961f6c3dfe128a3ef04f6a892f7df143374d 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api.cc
+++ b/chrome/browser/extensions/api/downloads/downloads_api.cc
@@ -167,7 +167,7 @@ const char kUrlRegexKey[] = "urlRegex";
 
 // Note: Any change to the danger type strings, should be accompanied by a
 // corresponding change to downloads.json.
-const char* kDangerStrings[] = {
+const char* const kDangerStrings[] = {
   kDangerSafe,
   kDangerFile,
   kDangerUrl,
@@ -183,7 +183,7 @@ COMPILE_ASSERT(arraysize(kDangerStrings) == content::DOWNLOAD_DANGER_TYPE_MAX,
 
 // Note: Any change to the state strings, should be accompanied by a
 // corresponding change to downloads.json.
-const char* kStateStrings[] = {
+const char* const kStateStrings[] = {
   kStateInProgress,
   kStateComplete,
   kStateInterrupted,
@@ -347,7 +347,8 @@ IconLoader::IconSize IconLoaderSizeFromPixelSize(int pixel_size) {
 
 typedef base::hash_map<std::string, DownloadQuery::FilterType> FilterTypeMap;
 
-void InitFilterTypeMap(FilterTypeMap& filter_types) {
+void InitFilterTypeMap(FilterTypeMap* filter_types_ptr) {
+  FilterTypeMap& filter_types = *filter_types_ptr;
   filter_types[kBytesReceivedKey] = DownloadQuery::FILTER_BYTES_RECEIVED;
   filter_types[kExistsKey] = DownloadQuery::FILTER_EXISTS;
   filter_types[kFilenameKey] = DownloadQuery::FILTER_FILENAME;
@@ -371,7 +372,8 @@ void InitFilterTypeMap(FilterTypeMap& filter_types) {
 
 typedef base::hash_map<std::string, DownloadQuery::SortType> SortTypeMap;
 
-void InitSortTypeMap(SortTypeMap& sorter_types) {
+void InitSortTypeMap(SortTypeMap* sorter_types_ptr) {
+  SortTypeMap& sorter_types = *sorter_types_ptr;
   sorter_types[kBytesReceivedKey] = DownloadQuery::SORT_BYTES_RECEIVED;
   sorter_types[kDangerKey] = DownloadQuery::SORT_DANGER;
   sorter_types[kEndTimeKey] = DownloadQuery::SORT_END_TIME;
@@ -454,8 +456,8 @@ void CompileDownloadQueryOrderBy(
   // comparisons.
   static base::LazyInstance<SortTypeMap> sorter_types =
     LAZY_INSTANCE_INITIALIZER;
-  if (sorter_types.Get().size() == 0)
-    InitSortTypeMap(sorter_types.Get());
+  if (sorter_types.Get().empty())
+    InitSortTypeMap(sorter_types.Pointer());
 
   for (std::vector<std::string>::const_iterator iter = order_by_strs.begin();
        iter != order_by_strs.end(); ++iter) {
@@ -487,8 +489,8 @@ void RunDownloadQuery(
   // comparisons.
   static base::LazyInstance<FilterTypeMap> filter_types =
     LAZY_INSTANCE_INITIALIZER;
-  if (filter_types.Get().size() == 0)
-    InitFilterTypeMap(filter_types.Get());
+  if (filter_types.Get().empty())
+    InitFilterTypeMap(filter_types.Pointer());
 
   DownloadQuery query_out;