Fix React Native createObjectURL polyfill incompatibility

[nitro404]

React Native introduces its own polyfill for window.URL.createObjectURL which is not compatible with Shaka. Encapsulating a reference to the original function inside of the MediaSourceEngine circumvents this issue.

Issue #1842

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[nitro404]

I signed the CLA.

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[shaka-bot]

Test Failure:

Generating Closure dependencies...
Linting JavaScript...

/var/lib/jenkins/workspace/Manual PR Test (local-tests)/test/media/media_source_engine_unit.js
164:1  error  Line 164 exceeds the maximum line length of 80  max-len
179:1  error  Line 179 exceeds the maximum line length of 80  max-len

✖ 2 problems (2 errors, 0 warnings)

END-BUILD: FAILURE
Build step 'Execute shell' marked build as failure

[joeyparrish]

@nitro404, can you please fix the linter errors? You can check this for yourself by running python build/all.py before pushing your commits.

[nitro404]

Should be fixed! I'm unfortunately not able to run "test.py" on my current environment, the script fails with an error, likely because I have Python 3 installed.

[joeyparrish]

Ah, yeah, those scripts currently require python2. If you have that, you can run python2 build/test.py.

But I'll run it through the build bot again.

[shaka-bot]

Test Failure:

Generating Closure dependencies...
Linting JavaScript...
Linting HTML...

Config loaded: /var/lib/jenkins/workspace/Manual PR Test (local-tests)/.htmlhintrc

Config loaded: /var/lib/jenkins/workspace/Manual PR Test (local-tests)/.htmlhintrc

Config loaded: /var/lib/jenkins/workspace/Manual PR Test (local-tests)/.htmlhintrc

Scanned 3 files, no errors found (22 ms).
Checking that the build files are complete...
Checking the tests for type errors...
/var/lib/jenkins/workspace/Manual PR Test (local-tests)/test/media/media_source_engine_unit.js:165: ERROR - Access to private property createObjectURL_ of shaka.media.MediaSourceEngine not allowed here.
shaka.media.MediaSourceEngine.createObjectURL_;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/var/lib/jenkins/workspace/Manual PR Test (local-tests)/test/media/media_source_engine_unit.js:180: ERROR - Access to private property createObjectURL_ of shaka.media.MediaSourceEngine not allowed here.
shaka.media.MediaSourceEngine.createObjectURL_ =
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/var/lib/jenkins/workspace/Manual PR Test (local-tests)/test/media/media_source_engine_unit.js:180: ERROR - constant property createObjectURL_ assigned a value more than once
shaka.media.MediaSourceEngine.createObjectURL_ =
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/var/lib/jenkins/workspace/Manual PR Test (local-tests)/test/media/media_source_engine_unit.js:192: ERROR - Access to private property createObjectURL_ of shaka.media.MediaSourceEngine not allowed here.
shaka.media.MediaSourceEngine.createObjectURL_ = originalCreateObjectURL;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

/var/lib/jenkins/workspace/Manual PR Test (local-tests)/test/media/media_source_engine_unit.js:192: ERROR - constant property createObjectURL_ assigned a value more than once
shaka.media.MediaSourceEngine.createObjectURL_ = originalCreateObjectURL;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

5 error(s), 0 warning(s), 91.7% typed
Build failed
END-BUILD: FAILURE
Build step 'Execute shell' marked build as failure

[joeyparrish]

For variables you reassign, use let instead of const. For the private access issue, you can make the member public (remove the @private annotation and the trailing underscore) and make it clear in the comments that it is for use by tests only.

[nitro404]

Ahh, sorry! I've adjusted my environment and fixed all outstanding issues. Updated the function description and re-based onto master as well. Let me know if any other changes are needed, thank you!

[joeyparrish]

Thanks! I've requested another test run through our build bot.

[shaka-bot]

All tests passed!

[joeyparrish]

Thank you for your contribution!