FLUID-4973: Fixed crash log "logActivity" on IE8 and removed unused utility "applyHostFunction". Some test cases for activity describing and logging in FluidJSTests.js
Merge remote-tracking branch 'amb26/FLUID-4973'

* amb26/FLUID-4973:
  FLUID-4973: Fixed crash log "logActivity" on IE8 and removed unused utility "applyHostFunction". Some test cases for activity describing and logging in FluidJSTests.js