WebRTC+libyuv: switch to use_allocator GYP variable.

masters/master.client.libyuv/master_builders_cfg.py

Index: masters/master.client.libyuv/master_builders_cfg.py
diff --git a/masters/master.client.libyuv/master_builders_cfg.py b/masters/master.client.libyuv/master_builders_cfg.py
index 1b4f9ba04b9b0ffec7cdbdaf51324cf4ff42d413..28f584c5b82f9d6eaa9aeda20342b8ff588728fe 100644
--- a/masters/master.client.libyuv/master_builders_cfg.py
+++ b/masters/master.client.libyuv/master_builders_cfg.py
@@ -49,9 +49,6 @@ mac_ios_factory_properties = {
     }
 }
 
-asan_gclient_env = {
-    'GYP_DEFINES': ('asan=1 release_extra_cflags=-g linux_use_tcmalloc=0 ')}
-
 # Windows.
 defaults['category'] = 'win'
 
@@ -158,7 +155,7 @@ F('mac_asan_factory', mac().LibyuvFactory(
     tests=test_targets,
     factory_properties={
         'asan': True,
-        'gclient_env': asan_gclient_env.copy(),
+        'gclient_env': {'GYP_DEFINES': 'asan=1 release_extra_cflags=-g'},
     }))
 
 B('iOS Debug', 'ios_debug_factory', scheduler=scheduler_name)
@@ -236,7 +233,9 @@ F('linux_asan_factory', linux().LibyuvFactory(
     tests=test_targets,
     factory_properties={
         'asan': True,
-        'gclient_env': asan_gclient_env.copy(),
+        'gclient_env': {
+            'GYP_DEFINES': 'asan=1 release_extra_cflags=-g use_allocator=none',
+        },
     }))
 
 # Android.