Ensure close is called in all use cases.

[yschimke]

A non local return from the inline function was skipping the close.

Addresses #1187

[swankjesse]

Ooooh I hate that this fix is necessary.

[yschimke]

Failure looks load+timeout related

okio.PipeTest[jvm] > sourceBlocksOnSlowWriter[jvm] FAILED
    java.lang.AssertionError: expected:<4000.0> but was:<4299.10836899979>
        at org.junit.Assert.fail(Assert.java:89)
        at org.junit.Assert.failNotEquals(Assert.java:835)
        at org.junit.Assert.assertEquals(Assert.java:555)
        at org.junit.Assert.assertEquals(Assert.java:685)
        at okio.PipeTest.assertElapsed(PipeTest.java:374)
        at okio.PipeTest.sourceBlocksOnSlowWriter(PipeTest.java:361)