Fix preview crash on local files during upload

[albendz]

Title (required)

Fixes App crashes when tapping on an image during multiple share #1653

Description (required)

Fixes App crashes when tapping on an image during multiple share #1653

• Add string length check in Utils.
• If file is local, set the URL to local URI.
• If there is no filename (i.e. local), do not try to fetch.

Tests performed (required)

Tested on Samsung Galaxy S6 Android 7.0 API 24, with Debug
Gradle build via AndroidStudio

Request from reviewer: Which build tasks do I run to do verification or is the default build from Android Studio sufficient?

[codecov-io]

Codecov Report

Merging #1696 into master will increase coverage by 0.02%.
The diff coverage is 25%.

@@            Coverage Diff            @@
##           master   #1696      +/-   ##
=========================================
+ Coverage    3.85%   3.87%   +0.02%     
=========================================
  Files         151     151              
  Lines        7604    7612       +8     
  Branches      714     716       +2     
=========================================
+ Hits          293     295       +2     
- Misses       7294    7300       +6     
  Partials       17      17

Impacted Files	Coverage Δ
...fr/free/nrw/commons/media/MediaDetailFragment.java	0% <0%> (ø)	⬆️
...n/java/fr/free/nrw/commons/MediaWikiImageView.java	0% <0%> (ø)	⬆️
app/src/main/java/fr/free/nrw/commons/Utils.java	26.15% <100%> (+2.34%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update d7b956e...de9c982. Read the comment docs.

[neslihanturan]

Thanks @albendz this works as intended :) Are you willing to also work on #1734 ? Since you get familiar with related codes.

[neslihanturan]

And, I didn't experienced the difficulty about " building with gradle due to dexcount plugin: KeepSafe/dexcount-gradle-plugin#234. In testing, disabled the plugin." you mentioned. Did you solve that problem?

[albendz]

I can take a look at #1734
I fixed the dexcount by not upgrading the gradle version when prompted by android studio. I hadn't realized this is what was causing my issues.