Issue - 134 : Fix for session leak issue

[anupbaldawa]

#134

Description:
Fixing the session leak issue. The session was removed from the reads_ or writes_ array but it was not added to borrowed_ array immediately. Due to which, there would be a time where a session is not present in either writes_ or reads_ or borrowed_. This causes the code to create new session as it concludes that 1 session is missing. Hence, the code is always creating session, maxing out the total connections to be made to spanner which eventually locks the database as we cannot create any new connections

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[codecov]

Codecov Report

Merging #135 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #135   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files          12     12           
  Lines        1394   1398    +4     
=====================================
+ Hits         1394   1398    +4

Impacted Files	Coverage Δ
src/session-pool.js	100% <100%> (ø)	⬆️

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[DuaneGarber]

We are working on getting the Corporate CLA set up on our side .... This should be ready in a few hours.

[anupbaldawa]

@callmehiphop Update the PR.

[anupbaldawa]

Corporate CLA was signed on Mar 05, 2018 11:04 PST

[googlebot]

So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this State. It's up to you to confirm consent of the commit author(s) and merge this pull request when appropriate.

[stephenplusplus]

@alexander-fenster we'll probably need help checking the CLA.

[alexander-fenster]

The bot complains that there are two people who contributed to this PR: the original author @anup-honey and @stephenplusplus who merged the latest changes from master to this branch. That may look a little bit weird but we need @anup-honey to confirm here that they are OK with their commits being merged :) @anup-honey, please reply OK here if so. After that, after @callmehiphop approves, we're good to go.

[stephenplusplus]

@alexander-fenster check the CLA bots logs so far, though. It doesn't seem to have ever recognized the CLA from @anup-honey.

Regarding the line: "stephenplusplus added the cla: yes label 5 days ago" -- no idea what that's about.

[anupbaldawa]

I signed the Corporate CLA on Mar 05, 2018 11:04 PST.
I confirmed that by going to https://cla.developers.google.com/clas.
Do you want me to push a fake/empty commit so that the bot can recognize my CLA?

[alexander-fenster]

@anup-honey @DuaneGarber you said you have signed the corporate CLA, what's the name of the corporation so that I could check it internally? Thanks!

[anupbaldawa]

@alexander-fenster The name is "Honey Science Corporation"

[alexander-fenster]

@anup-honey Yes, then you're good to go. Just waiting for @callmehiphop to approve the changes :) Thanks!