Enable multidex on more Android targets

Bug: 807936
Change-Id: Iba1bf251aa822753251768deeea02e809cc93860
Reviewed-on: https://chromium-review.googlesource.com/897667Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Juan Antonio Navarro Pérez <perezju@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533735}

content/test/BUILD.gn

@@ -993,6 +993,7 @@ test("content_browsertests") {
   }
 
   if (is_android) {
+    enable_multidex = true
     if (is_component_build) {
       sources += [ "../browser/android/render_widget_host_connector.cc" ]
     }