Fix array to string conversion in REST::sendRequest()

[mcrumm]

Minimum viable test for an array to string conversion error in REST::sendRequest().

Before:

$ vendor/bin/phpunit
PHPUnit 4.8.23 by Sebastian Bergmann and contributors.

........................E.............

Time: 178 ms, Memory: 8.00Mb

There was 1 error:

1) Google\Gcloud\Tests\Storage\Connection\RESTTest::testGetObjectReturnsResponseArray
Array to string conversion

/Users/mike/Code/mcrumm/gcloud-php/src/Storage/Connection/REST.php:263
/Users/mike/Code/mcrumm/gcloud-php/src/Storage/Connection/REST.php:152
/Users/mike/Code/mcrumm/gcloud-php/tests/Storage/Connection/RESTTest.php:39

FAILURES!
Tests: 38, Assertions: 40, Errors: 1.

FWIW, I found this repo last night while looking for a flysystem adapter for GCP. Not finding one that I liked, I set out to write one using gcloud-php as its base. This was the last of the issues I encountered while working on the initial implementation.

[dwsupplee]

Thanks again @mcrumm! Happy to merge this and excited to hear about your plans to use the library. :)

[mcrumm]

@dwsupplee I'm not sure what HHVM is complaining about, here. Any thoughts?

[dwsupplee]

Yes, I believe it has to do with this line: https://github.com/GoogleCloudPlatform/gcloud-php/blob/master/src/Storage/Connection/REST.php#L228

Changing it to __DIR__ . '/ServiceDefinition/storage-v1.json' should do the trick. I will work quickly on getting my latest work up, it's got fixes for items like this as well as some restructuring to make tests easier to write.

[mcrumm]

Yep, that got hhvm to pass. I can roll that change back if it will conflict with your other work, and rebase when the time is right.

[dwsupplee]

It's no problem, this is good to merge. Thanks again!