Include only current votes into change message when removing a reviewer

Change-Id: I541d7f7b130a40811f398910169e493acc212537
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
Set http queue size to max integer when maxQueued 0 is provided

In 8e78797190ddb9e04f93190bae86fe3956f08b3d, in migration change from
Jetty 8 to Jetty 9 one special case was missing: maxQueued = 0. By
mapping this value to max capacity of the queue without extra check
for the 0 value makes Jetty fail to start with IllegalArgumentException
when httpd.minThreads (default 5) smaller then maxQueued.

Rectify it by assigning Integer.MAX_VALUE to maxQueued when 0 was set.
Adjust the documenatation to reflect this change.

Change-Id: I686cf75a0bd0af16983e52ba22e7957a65cbb5b9
Merge "Set http queue size to max integer when maxQueued 0 is provided" into stable-2.9
Refactor MergeabilityChecker to use a builder pattern

This class was growing with various permutations of change, project,
branch, sync/async, which are suited to constructing with a Builder.
We also want to add a priority flag to certain checks to support more
fine-grained scheduling.

In general, due to the strategy of kicking off async work that can
fan out and ignoring errors, try to log errors as they happen instead
of depending on callers to call get() on the resulting Futures.

Change-Id: Ia575793e5ceb5aa3148b45a9a49e4e10e50a5108
Split mergeability checks by priority

When a project config is updated or a change is merged, all open
changes on an entire project or branch need to be rechecked for
mergeability. For projects or branches with lots of open changes,
this can flood the queue with potentially slow checks. This will
block simpler cases, such as checking mergeability of a single change
during ReceiveCommits.

Define a new Priority enum on the MergeabilityChecksExecutor so we
can split the queue based on priority, allowing smaller, interactive
changes such as pushes to not wait for the entire queued backlog.

Change-Id: I57f9eb33dbbcd8a560adfe4458ce48d7b0817957