Fix ANGLE build with extended clang warnings

Add newline-eof to the list of ignroed warnings.
Fix shadowed fields.

Bug: skia:
Change-Id: I4985ce2495194a7f805af98c4f42c44691086e36
Reviewed-on: https://skia-review.googlesource.com/79681
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
diff --git a/gn/BUILD.gn b/gn/BUILD.gn
index 57cb5da..7791c1b 100644
--- a/gn/BUILD.gn
+++ b/gn/BUILD.gn
@@ -369,6 +369,7 @@
       "-Wno-missing-noreturn",
       "-Wno-old-style-cast",
       "-Wno-padded",
+      "-Wno-newline-eof",
     ]
     cflags_cc += [
       "-Wno-c++98-compat",