Fix compilation of Enum on JDK 7

Change-Id: I2e58b6a527e4ef1fc7ed3359b8aea88d01a031fb

libcore: Better Enum fix for JDK 7

 * Jerome Pilliet suggests using a cast in the compareTo method instead of
   changing the field visibility. This is a much better fix.

Change-Id: I334105e0922225512a4d0a2d4b6c9c6ec71b9c51
GC triggering performance optimizations

Copy the correct starting heap size at process init.
Interfaces to set GC/managed heap parameters.

Change-Id: If0b1637291e77f9781ae6249c5d0257f659253ca
Fixed possible file handle leak
Automatically flush the cache when an edit is completed.

This will remove the need for applications to manually flush
the cache.
Synchronize isClosed.

See https://github.com/square/okhttp/issues/151

Conflicts:
	src/main/java/com/jakewharton/disklrucache/DiskLruCache.java
Add getLength method to Snapshot

Conflicts:
	luni/src/main/java/libcore/io/DiskLruCache.java
Test that timeouts are respected on recycled connections.

This is a renamed version of testGetKeepAlive, which wasn't
testing very much in its old form.

Change-Id: I08c46f577741817b7de714d362f3426d17984042

Conflicts:
	luni/src/test/java/libcore/java/net/URLConnectionTest.java
Revert "Don't force x86 devices to run an insanely long test."

This reverts commit 0cfb7262e5ea1bfaa745cf24e60751c86d5c7164.
Revert "If libcore wants ASCII casing, it needs to ask for it like everyone else."

This reverts commit 0e352cd20497123ade3aa4caf30248e10df69ab1.