Add use_allocator instead of linux_use_tcmalloc to switch the allocator.

base/base.gyp

Index: base/base.gyp
diff --git a/base/base.gyp b/base/base.gyp
index e50e84004835d97771287983e3d4db79059c2aaf..cd8f488fa43a252f4e5dfbe9778eb1fed00d2958 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -180,7 +180,8 @@
             ],
           },
           'conditions': [
-            ['linux_use_tcmalloc==0', {
+            # TODO(dmikurube): Kill linux_use_tcmalloc. http://crbug.com/345554
+            ['use_allocator!="tcmalloc" and (use_allocator!="see_use_tcmalloc" or linux_use_tcmalloc==0)', {
               'defines': [
                 'NO_TCMALLOC',
               ],
@@ -756,7 +757,8 @@
             'message_loop/message_pump_glib_unittest.cc',
           ]
         }],
-        ['OS == "linux" and linux_use_tcmalloc==1', {
+        # TODO(dmikurube): Kill linux_use_tcmalloc. http://crbug.com/345554
+        ['OS == "linux" and ((use_allocator!="none" and use_allocator!="see_use_tcmalloc") or (use_allocator=="see_use_tcmalloc" and linux_use_tcmalloc==1))', {
             'dependencies': [
               'allocator/allocator.gyp:allocator',
             ],