Logging generic type as String causes unexpected lint failure

Running lint on the following code causes an "unexpected failure."

``` java
public class Foo {

public void logBar(T bar) {
Timber.d("bar: %s", bar);
}
}
```

The error message is:

```
Unexpected failure during lint analysis of Foo.java (this is a bug in lint or one of the libraries it depends on)
EcjParser.equalsCompound(EcjParser.java:2351)->EcjParser$EcjResolvedClass.isSubclassOf(EcjParser.java:1381)->WrongTimberUsageDetector.isSubclassOf(WrongTimberUsageDetector.java:329)->WrongTimberUsageDetector.checkThrowablePosition(WrongTimberUsageDetector.java:448)
```

The failure message goes away if we replace `Timber.d("bar: %s", bar);` with `Timber.d("bar: %s", bar.toString());`. It seems like lint isn't able to recognize the implicit `toString()` method call.

Furthermore, I'm seeing this issue for the Gradle plugin version `1.5.0`. Using the plugin version `1.3.1` also makes the failure message disappear.

Here's an [example app](https://github.com/mattlogan/TimberBug) with this issue.

Reproduce the failure in the linked TimberBug example app using Gradle plugin 1.5.0 and the Foo.java snippet. Start with the stack trace entries in WrongTimberUsageDetector.checkThrowablePosition and EcjParser.equalsCompound; done means lint completes without an unexpected failure for the generic type passed to Timber.d.

Written by the indexing model from the issue text.