[Android] Add vectorDrawables.useSupportLibrary to build.gradle

This CL adds "vectorDrawables.useSupportLibrary = true" to build.gradle
that is used by Android Studio to fix warning issued for XML
app:srcCompat attribute. Chromium build already uses support library
for vector drawables.

Bug: 620034
Change-Id: I92fb56f83f854de42577a13c3fe8d51b5d1fe263
Reviewed-on: https://chromium-review.googlesource.com/668401
Reviewed-by: Peter Wen <wnwen@chromium.org>
Commit-Queue: Boris Sazonov <bsazonov@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#502590}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: c182fd2bbdaedfe3caa046fcb849ae5c35745b0c

android/gradle/android.jinja

@@ -82,6 +82,10 @@ android {
 {{ expand_sourceset(test, 'test') }}
 {{ expand_sourceset(android_test, 'androidTest') }}
     }
+
+    defaultConfig {
+        vectorDrawables.useSupportLibrary = true
+    }
 }
 
 {% include 'dependencies.jinja' %}