Fix deadlock in Android's font deserializer.

git-svn-id: http://skia.googlecode.com/svn/trunk@3551 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/ports/SkFontHost_android.cpp b/src/ports/SkFontHost_android.cpp
index edbc016..230e990 100644
--- a/src/ports/SkFontHost_android.cpp
+++ b/src/ports/SkFontHost_android.cpp
@@ -745,9 +745,10 @@
 }
 
 SkTypeface* SkFontHost::Deserialize(SkStream* stream) {
-    SkAutoMutexAcquire  ac(gFamilyHeadAndNameListMutex);
-
-    load_system_fonts();
+    {
+        SkAutoMutexAcquire  ac(gFamilyHeadAndNameListMutex);
+        load_system_fonts();
+    }
 
     // check if the font is a custom or system font
     bool isCustomFont = stream->readBool();