grpc: export MethodHandler #7794

[mohdjishin]

Made MethodHandler type exportable

• Updated MethodHandler to be exportable for external use.
• Modified MethodDesc struct to reference the exportable MethodHandler type.

Issue #7794

RELEASE NOTES:

• grpc: export MethodHandler, which is the type of an already-exported field in MethodDesc

[linux-foundation-easycla]

• ✅login: mohdjishin / (500e8c0)
• ✅login: mohdjishin / (500e8c0, 668704d)

The committers listed above are authorized under a signed CLA.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.78%. Comparing base (d66fc3a) to head (668704d).
Report is 13 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7796      +/-   ##
==========================================
+ Coverage   81.71%   81.78%   +0.07%     
==========================================
  Files         374      374              
  Lines       38166    38166              
==========================================
+ Hits        31188    31215      +27     
+ Misses       5699     5691       -8     
+ Partials     1279     1260      -19     

Files with missing lines	Coverage Δ
server.go	82.00% <ø> (-0.08%)	⬇️

... and 21 files with indirect coverage changes

[aranjans]

LGTM, adding @dfawley for second reviewer as he is part of the earlier discussion happened for the mentioned issue.

[dfawley]

@mohdjishin please sign the CLA so we can merge this.

[mohdjishin]

@mohdjishin please sign the CLA so we can merge this.

signed @dfawley