Various optimizations to reduce the number of temporary allocations.

chrome/browser/themes/browser_theme_pack.cc

Index: chrome/browser/themes/browser_theme_pack.cc
diff --git a/chrome/browser/themes/browser_theme_pack.cc b/chrome/browser/themes/browser_theme_pack.cc
index fe2f645cb496e972096827d983f38a0818de9092..ab80732b0493b943bf988664ed1311d597a0bf8e 100644
--- a/chrome/browser/themes/browser_theme_pack.cc
+++ b/chrome/browser/themes/browser_theme_pack.cc
@@ -779,18 +779,18 @@ scoped_refptr<BrowserThemePack> BrowserThemePack::BuildFromDataPack(
 }
 
 // static
-void BrowserThemePack::GetThemeableImageIDRs(std::set<int>* result) {
-  if (!result)
-    return;
-
-  result->clear();
+bool BrowserThemePack::IsPersistentImageID(int id) {
   for (size_t i = 0; i < kPersistingImagesLength; ++i)
-    result->insert(kPersistingImages[i].idr_id);
+    if (kPersistingImages[i].idr_id == id)
+      return true;
 
 #if defined(USE_ASH) && !defined(OS_CHROMEOS)
   for (size_t i = 0; i < kPersistingImagesDesktopAuraLength; ++i)
-    result->insert(kPersistingImagesDesktopAura[i].idr_id);
+    if (kPersistingImagesDesktopAura[i].idr_id == id)
+      return true;
 #endif
+
+  return false;
 }
 
 bool BrowserThemePack::WriteToDisk(const base::FilePath& path) const {