Memory warning datasource

[leandro-godon]

Goal

Send the Low Memory Warnings as span events.

Removal of warnings in PerformanceInfo will be in a different PR.

Testing

Tested against the production dashboard, verified that the events were visible.

[codecov]

Codecov Report

Attention: Patch coverage is 96.29630% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 80.64%. Comparing base (53461e0) to head (4a6afc5).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #731      +/-   ##
==========================================
- Coverage   80.65%   80.64%   -0.02%     
==========================================
  Files         423      424       +1     
  Lines       11148    11173      +25     
  Branches     1671     1672       +1     
==========================================
+ Hits         8991     9010      +19     
- Misses       1452     1459       +7     
+ Partials      705      704       -1     

Files	Coverage Δ
.../embrace/android/embracesdk/arch/schema/EmbType.kt	58.82% <100.00%> (+1.24%)	⬆️
...brace/android/embracesdk/arch/schema/SchemaType.kt	72.22% <100.00%> (+0.63%)	⬆️
...bracesdk/capture/memory/MemoryWarningDataSource.kt	100.00% <100.00%> (ø)
...d/embracesdk/injection/DataCaptureServiceModule.kt	98.11% <100.00%> (ø)
...e/android/embracesdk/injection/DataSourceModule.kt	100.00% <100.00%> (ø)
.../embracesdk/capture/memory/EmbraceMemoryService.kt	92.30% <66.66%> (-7.70%)	⬇️

... and 8 files with indirect coverage changes

[fractalwrench]

Looks good but this is missing an integration test that verifies the feature is working as we'd expect. As there isn't a public API for triggering a memory warning it'd be ok to add a shim to trigger a memory warning.

[leandro-godon]

Added an integration test.

[fractalwrench]

LGTM