[opt-viewer] Make it work in the absence of hotness information
[opt-viewer] Make it work in the absence of hotness information

In this case the index page is sorted by the source location.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@286572 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit 29e16233238682b178a52528033ffa990df3ae0f)

apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm,apple/swift-llvm