Fix for compatibility issue with Android compiler.

Change-Id: Iaa5f28535d107cb3564437b0109186a0584ae917
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/192340
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/dawn/native/opengl/DeviceGL.h b/src/dawn/native/opengl/DeviceGL.h
index b11409a..1e943fe 100644
--- a/src/dawn/native/opengl/DeviceGL.h
+++ b/src/dawn/native/opengl/DeviceGL.h
@@ -143,7 +143,7 @@
     const OpenGLFunctions mGL;
 
     GLFormatTable mFormatTable;
-    std::unique_ptr<ContextEGL> mContext = nullptr;
+    std::unique_ptr<ContextEGL> mContext;
     int mMaxTextureMaxAnisotropy = 0;
 };