[gmscore] Enable multidexing for various test targets

android_webview/test/BUILD.gn

Index: android_webview/test/BUILD.gn
diff --git a/android_webview/test/BUILD.gn b/android_webview/test/BUILD.gn
index 00db3efb3dd3fe0e3e6060979b8e66449f1449f1..5e82e2b3d86ec5cd2e950899d485a68630a963fe 100644
--- a/android_webview/test/BUILD.gn
+++ b/android_webview/test/BUILD.gn
@@ -52,6 +52,8 @@ android_apk("android_webview_apk") {
   _native_lib_file =
       rebase_path("$root_gen_dir/CHROME_VERSION.json", root_build_dir)
   native_lib_version_arg = "@FileArg($_native_lib_file:full-quoted)"
+
+  enable_multidex = true
 }
 
 android_resources("android_webview_apk_resources") {
@@ -211,6 +213,9 @@ test("android_webview_unittests") {
   # Tests do not require any data, but our dependencies pull a lot in.
   ignore_all_data_deps = true
 
+  # Dependencies (e.g. Play services) make the binary reach the dex limit.
+  enable_multidex = true
+
   deps = [
     ":android_webview_unittests_assets",
     ":android_webview_unittests_java",