[Coverage] Update CSS to make HTML reports copy-paste friendly.
[Coverage] Update CSS to make HTML reports copy-paste friendly.

Summary:
This minor change allows to copy snippets from HTML reports so they
will be pasted in the following format:
%LineNumber%\t%HitCount%\t%CodeLine%

rather then being split onto multiple lines. To see this in action, try copy
pasting from https://chromium-coverage.appspot.com/reports/560344/linux/chromium/src/third_party/zlib/compress.c.html

Requested in https://bugs.chromium.org/p/chromium/issues/detail?id=845571

Reviewers: vsk

Reviewed By: vsk

Subscribers: llvm-commits, morehouse, kcc

Differential Revision: https://reviews.llvm.org/D47231

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@333034 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm