Add isRemote check for context propagation

[vishweshbankwar]

Fixes #3315

Changes

Please provide a brief description of the changes here.

For significant contributions please make sure you have completed the following items:

• Appropriate CHANGELOG.md updated for non-trivial changes
• Design discussion issue #
• Changes in public API reviewed

[codecov]

Codecov Report

Merging #3329 (fb2d5a6) into main (a2aa305) will decrease coverage by 0.16%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #3329      +/-   ##
==========================================
- Coverage   85.44%   85.27%   -0.17%     
==========================================
  Files         270      270              
  Lines        9561     9561              
==========================================
- Hits         8169     8153      -16     
- Misses       1392     1408      +16     

Impacted Files	Coverage Δ
src/OpenTelemetry/Trace/TracerProviderSdk.cs	96.40% <100.00%> (ø)
...entation/ExportClient/OtlpGrpcTraceExportClient.cs	50.00% <0.00%> (-28.58%)	⬇️
...xporter.OpenTelemetryProtocol/OtlpTraceExporter.cs	59.09% <0.00%> (-18.19%)	⬇️
...metryProtocol/Implementation/ActivityExtensions.cs	91.20% <0.00%> (-4.40%)	⬇️
...Telemetry/Internal/SelfDiagnosticsEventListener.cs	96.87% <0.00%> (-0.79%)	⬇️
...ZPages/Implementation/ZPagesExporterEventSource.cs	62.50% <0.00%> (+6.25%)	⬆️

[reyang]

This is semantically buggy, I guess?

Maybe:

var isRootSpan = traceId == default;

return isRootSpan || isParentRemote
    ? ...

[cijothomas]

TracerProvider modified to create activity irrespective of SamplingResult, for spans with Remote Parent, to maintain context propagation.

^ or similar wording.

[cijothomas]

@vishweshbankwar will hold off from merging for a day, as we are doing 1.3.0 stable release, and want to avoid any functional changes.

[cijothomas]

@vishweshbankwar Please fix the conflict, and we are good to go

[utpilla]

We could probably explore updating the method signature here to something like this:
private static ActivitySamplingResult PropagateOrIgnoreData(in ActivityContext parentContext) and pass in options.Parent to this method. ActivityContext is a readonly struct so using the in modifier might give some minor perf gains.

[vishweshbankwar]

Minor:

Method	Mean	Error	StdDev
WithoutInParam	716.8 ns	12.69 ns	11.87 ns
WithInparam	676.5 ns	7.27 ns	6.44 ns

I have updated the method signature