Remove `DanglingUntriaged` on InstanceBase.mPlatform

This patch removes `DanglingUntriaged` on InstanceBase.mPlatform
after the fix in Chromium has been merged. Now In Chromium
Instance->DisconnectDawnPlatform() will be called in
WebGPUDecoderImpl::Destroy().

Bug: dawn:2349
Change-Id: I72be1c18fe9b874ef20ddb0bdb5fb6d13125edee
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/181640
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
diff --git a/src/dawn/native/Instance.h b/src/dawn/native/Instance.h
index f243abb..1f106ed 100644
--- a/src/dawn/native/Instance.h
+++ b/src/dawn/native/Instance.h
@@ -216,8 +216,7 @@
     raw_ptr<void> mLoggingCallbackUserdata = nullptr;
 
     std::unique_ptr<dawn::platform::Platform> mDefaultPlatform;
-    // TODO(https://crbug.com/dawn/2349): Investigate DanglingUntriaged in dawn/native.
-    raw_ptr<dawn::platform::Platform, DanglingUntriaged> mPlatform = nullptr;
+    raw_ptr<dawn::platform::Platform> mPlatform = nullptr;
 
     BackendsArray mBackends;
     BackendsBitset mBackendsTried;