add blink_disable_partition_allocator for memory profiler.

Source/config.gyp

Index: Source/config.gyp
diff --git a/Source/config.gyp b/Source/config.gyp
index eb9fbccd631e3bb6b2797271ea04756495ab12ce..b4017b5b732e8f3c5f7853ffd6fbe50f5df428e5 100644
--- a/Source/config.gyp
+++ b/Source/config.gyp
@@ -39,6 +39,10 @@
     # If set to 1 together with blink_gc_plugin, the Blink GC plugin will dump
     # points-to graph files for each compilation unit.
     'blink_gc_plugin_dump_graph%': 0,
+    # If set to 1, the Blink will use the base allocator instead of
+    # PartitionAlloc. so that the top of stack-unwinding becomes the caller
+    # which requests memory allocation in blink.
+    'blink_disable_partition_allocator%': 0,
   },
   'targets': [
   {
@@ -109,6 +113,11 @@
             'OTHER_CFLAGS': ['<!@(../../../tools/clang/scripts/blink_gc_plugin_flags.sh enable-oilpan=<(enable_oilpan) dump-graph=<(blink_gc_plugin_dump_graph))'],
           },
         }],
+        ['blink_disable_partition_allocator==1', {
+          'defines': [
+            'MEMORY_TOOL_REPLACES_ALLOCATOR',
+          ],
+        }],
       ],
     },
   },