Re-landing "Refactoring cl::list_storage from "is a" to "has a" std::vector."
Re-landing "Refactoring cl::list_storage from "is a" to "has a" std::vector."

Originally landed r238485

MSVC resolves identifiers differently from Clang and GCC, this resulted in build bot failures. This pach re-lands r238485 and fixes the build failures.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@238505 91177308-0d34-0410-b5e6-96231b3b80d8

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