generate_gradle.py: fix closing of 'sourceSets' block.

The 'sourceSets' block adds '{' symbol without any conditions. But related '}' symbol is added under some 'if' statement. So there is set of input params with which 'generate_gradle.py' doesn't closes 'sourceSets'.
The solution is moving '}' under conditions.

R=agrieve@chromium.org

Change-Id: I82a3998cf9e4c06b43eefa43400d084fa3a6d833
Reviewed-on: https://chromium-review.googlesource.com/962445Reviewed-by: agrieve <agrieve@chromium.org>
Commit-Queue: agrieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543076}

build/android/gradle/android.jinja

@@ -75,8 +75,8 @@ android {
 {% for t in android_test %}
 {{ expand_sourceset(t, 'androidTest') }}
 {% endfor %}
-    }
 {% endif %}
+    }
 
     defaultConfig {
         vectorDrawables.useSupportLibrary = true