[gin] Replace ArrayBuffer::Private with v8::BackingStore

v8::BackingStore simplifies the lifetime management so there is no
need to install weak callbacks.

Bug: 1008840
Change-Id: I8c183c87166a2f496baef7ec2ab44346741e867d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2676542
Commit-Queue: Ulan Degenbaev <[email protected]>
Reviewed-by: Andreas Haas <[email protected]>
Reviewed-by: Ross McIlroy <[email protected]>
Reviewed-by: Daniel Cheng <[email protected]>
Cr-Commit-Position: refs/heads/master@{#852616}
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 5aca1190..9857b18 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -719,9 +719,12 @@
         'std::shared_ptr should not be used. Use scoped_refptr instead.',
       ),
       True,
-      ['^third_party/blink/renderer/core/typed_arrays/array_buffer/' +
+      [
+       # Needed for interop with third-party library.
+       '^third_party/blink/renderer/core/typed_arrays/array_buffer/' +
          'array_buffer_contents\.(cc|h)',
-       # Needed for interop with third-party library
+       'gin/array_buffer.cc',
+       'gin/array_buffer.h',
        'chrome/services/sharing/nearby/',
        _THIRD_PARTY_EXCEPT_BLINK],  # Not an error in third_party folders.
     ),