[Wconversion] Suppress warnings

Bug: 58162
Change-Id: I29c8440b70ebb748297b3505b7e2e5a25309703c
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/flatbuffers/+/425961
Reviewed-by: Roland McGrath <mcgrathr@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index 7953b13..8f75bdc 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -24,6 +24,9 @@
   # TODO(46773): UBSan has found an instance of undefined behavior in this target.
   # Disable UBSan for this target temporarily until it is migrated into CI/CQ.
   public_configs += [ "//build/config:temporarily_disable_ubsan_do_not_use" ]
+
+  # TODO(fxb/58162): delete the below and fix compiler warnings
+  configs += [ "//build/config:Wno-conversion" ]
 }
 
 source_set("compiler_files") {
@@ -51,15 +54,14 @@
   ]
   include_dirs = [ "grpc" ]
   visibility = [ ":*" ]
-  deps = [
-    ":flatbuffers",
-  ]
+  deps = [ ":flatbuffers" ]
+
+  # TODO(fxb/58162): delete the below and fix compiler warnings
+  configs += [ "//build/config:Wno-conversion" ]
 }
 
 executable("flatc") {
-  sources = [
-    "src/flatc.cpp",
-  ]
+  sources = [ "src/flatc.cpp" ]
   deps = [
     ":compiler_files",
     ":flatbuffers",