Remove dependency on allocator from 'content' targets

base/allocator/BUILD.gn

Index: base/allocator/BUILD.gn
diff --git a/base/allocator/BUILD.gn b/base/allocator/BUILD.gn
index 1d0ba62cb88769892c6531d317b9e8b5243f0273..cfb797b38e9d9873772b39813db98e96de1e8673 100644
--- a/base/allocator/BUILD.gn
+++ b/base/allocator/BUILD.gn
@@ -202,6 +202,7 @@ if (use_allocator == "tcmalloc") {
       "$tcmalloc_dir/src/windows/port.cc",
       "$tcmalloc_dir/src/windows/port.h",
       "debugallocation_shim.cc",
+      "tcmalloc_extension.cc",
 
       # These are both #included by allocator_shim for maximal linking.
       #"generic_allocators.cc",
@@ -287,6 +288,9 @@ if (use_allocator == "tcmalloc") {
         "-Wl,-u_Z21InitialMallocHook_NewPKvj,-u_Z22InitialMallocHook_MMapPKvS0_jiiix,-u_Z22InitialMallocHook_SbrkPKvi",
         "-Wl,-u_Z21InitialMallocHook_NewPKvm,-u_Z22InitialMallocHook_MMapPKvS0_miiil,-u_Z22InitialMallocHook_SbrkPKvl",
         "-Wl,-u_ZN15HeapLeakChecker12IgnoreObjectEPKv,-u_ZN15HeapLeakChecker14UnIgnoreObjectEPKv",
+
+        # For InitializeAllocatorWeak function implementation for tcmalloc.
+        "-Wl,-u_ZN4base9allocator23InitializeAllocatorWeakEv",
       ]
     }