unchecked_malloc() for Skia on OSX.

base/process_util_mac.mm

Index: base/process_util_mac.mm
diff --git a/base/process_util_mac.mm b/base/process_util_mac.mm
index b257021401726975aa33eb3fc7cc96b140964141..e20f8bf5528eb37ffe2c0cfada8cab0f2435a630 100644
--- a/base/process_util_mac.mm
+++ b/base/process_util_mac.mm
@@ -836,16 +836,10 @@ id oom_killer_allocWithZone(id self, SEL _cmd, NSZone* zone)
 
 }  // namespace
 
-malloc_zone_t* GetPurgeableZone() {
-  // malloc_default_purgeable_zone only exists on >= 10.6. Use dlsym to grab it
-  // at runtime because it may not be present in the SDK used for compilation.
-  typedef malloc_zone_t* (*malloc_default_purgeable_zone_t)(void);
-  malloc_default_purgeable_zone_t malloc_purgeable_zone =
-      reinterpret_cast<malloc_default_purgeable_zone_t>(
-          dlsym(RTLD_DEFAULT, "malloc_default_purgeable_zone"));
-  if (malloc_purgeable_zone)
-    return malloc_purgeable_zone();
-  return NULL;
+void* oom_safe_malloc(size_t size) {
+  if (g_old_malloc)
+    return g_old_malloc(malloc_default_zone(), size);
+  return malloc(size);
 }
 
 void EnableTerminationOnOutOfMemory() {
@@ -880,7 +874,7 @@ void EnableTerminationOnOutOfMemory() {
   ChromeMallocZone* default_zone =
       reinterpret_cast<ChromeMallocZone*>(malloc_default_zone());
   ChromeMallocZone* purgeable_zone =
-      reinterpret_cast<ChromeMallocZone*>(GetPurgeableZone());
+      reinterpret_cast<ChromeMallocZone*>(malloc_default_purgeable_zone());
 
   vm_address_t page_start_default = 0;
   vm_address_t page_start_purgeable = 0;