In the AST reader, keep track of the total number of source locations entries incrementally, rather than iterating over the chain when loading a single AST file.
In the AST reader, keep track of the total number of source locations
entries incrementally, rather than iterating over the chain when
loading a single AST file.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@135692 91177308-0d34-0410-b5e6-96231b3b80d8

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