Parameter Name Fixes

Context: dotnet/android#893 (comment)

The initial API-26 import didn't have ideal parameter names, as the
Android API documentation wasn't available, and the original API-26
`android.jar` wasn't compiled with `javac -parameters`, which
preserves parameter name information within the `.class` files.

This has apparently since changed: `class-parse` is now able to
extract parameter name information (perhaps an older `class-pasrse`
was previously used?), which allows us to get useful parameter names
for a large number of members instead of `p0`/`p1`/etc.

Since parameter names are used as `*EventArgs` member names, changing
parameter names can cause a large "ripple effect" in bindings.

xamarin-android PR #893 updates the `api-26.xml.in` file which
produces the v8.0 binding, including parameter name improvments.

Update `reference/Mono.Android.xml` to track the updated parameter
name information.

Author: jonpryor