Merging r339281:

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r339281 | ctopper | 2018-08-08 21:14:23 +0200 (Wed, 08 Aug 2018) | 5 lines

[CodeGen][Timers] Enable llvm::TimePassesIsEnabled when -ftime-report is specified

r330571 added a new FrontendTimesIsEnabled variable and replaced many usages of llvm::TimePassesIsEnabled. Including the place that set llvm::TimePassesIsEnabled for -ftime-report. The effect of this is that -ftime-report now only contains the timers specifically referenced in CodeGenAction.cpp and none of the timers in the backend.

This commit adds back the assignment, but otherwise leaves everything else unchanged.
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_70@339341 91177308-0d34-0410-b5e6-96231b3b80d8