gn2bp: Fix C++ warning showing up as errors when compiling cronet tests

Test: m
Change-Id: Id48dabf893fb7dc7698973f8d52a802134d77e82
diff --git a/tools/gn2bp/Android.bp.swp b/tools/gn2bp/Android.bp.swp
index eb0f9dc..7dbeda1 100644
--- a/tools/gn2bp/Android.bp.swp
+++ b/tools/gn2bp/Android.bp.swp
@@ -4341,6 +4341,7 @@
     cflags: [
         "-DGOOGLE_PROTOBUF_NO_RTTI",
         "-Wno-ambiguous-reversed-operator",
+        "-Wno-c++11-narrowing",
         "-Wno-error=return-type",
         "-Wno-macro-redefined",
         "-Wno-missing-field-initializers",
diff --git a/tools/gn2bp/gen_android_bp b/tools/gn2bp/gen_android_bp
index d33dc32..5cbd6e2 100755
--- a/tools/gn2bp/gen_android_bp
+++ b/tools/gn2bp/gen_android_bp
@@ -1673,6 +1673,7 @@
       '-Wno-ambiguous-reversed-operator', # needed for icui18n
       '-Wno-unreachable-code-loop-increment', # needed for icui18n
       '-fPIC',
+      '-Wno-c++11-narrowing',
   ]
   # Chromium builds do not add a dependency for headers found inside the
   # sysroot, so they are added globally via defaults.