Actually you get all sorts of crazy Gradle errors when trying to build Android Studio projects with Java 8, like
2016-04-10 17:50:49,401 [1624477] WARN - nal.AbstractExternalSystemTask - Gradle 2.10 requires Java 6 or later to run. Your build is currently configured to use Java 5.
com.intellij.openapi.externalSystem.model.ExternalSystemException: Gradle 2.10 requires Java 6 or later to run. Your build is currently configured to use Java 5.
As soon as I switched the default JDK to Java 7 it works fine. Looks like running Android Studio itself with Java SE 8 is tolerated, but building Android apps via Gradle with it only works well with Java 7.