Bug 1524688: Part 64 - Reduce component manager allocations. r=froydnj

With most of the JS components converted to static registration, the string
arena and component hashtables are much smaller than the minimum space we
allocate for them.

Differential Revision: https://phabricator.services.mozilla.com/D18474

--HG--
extra : source : 81dc12cc9257ba9c8f2eef578d99b142220b37a3
extra : histedit_source : 6f64bcd954cbc4db6970acfb5ed81717c739d13f

xpcom/components/nsComponentManager.cpp

@@ -338,7 +338,7 @@ nsresult nsComponentManagerImpl::Create(nsISupports* aOuter, REFNSIID aIID,
   return gComponentManager->QueryInterface(aIID, aResult);
 }
 
-static const int CONTRACTID_HASHTABLE_INITIAL_LENGTH = 128;
+static const int CONTRACTID_HASHTABLE_INITIAL_LENGTH = 32;
 
 nsComponentManagerImpl::nsComponentManagerImpl()
     : mFactories(CONTRACTID_HASHTABLE_INITIAL_LENGTH),

xpcom/components/nsComponentManager.h

@@ -269,7 +269,7 @@ class nsComponentManagerImpl final : public nsIComponentManager,
     SHUTDOWN_COMPLETE
   } mStatus;
 
-  mozilla::ArenaAllocator<1024 * 8, 8> mArena;
+  mozilla::ArenaAllocator<1024 * 1, 8> mArena;
 
   struct PendingServiceInfo {
     const nsCID* cid;