[PATCH] [compiler-rt] [asan] Refactor DescribeAddressIfStack to allow reuse for debugging API

[Alexey Samsonov]

LGTM modulo nit below.

================
Comment at: lib/asan/asan_report.cc:358
@@ +357,3 @@
+    p++;
+    vars->push_back({beg, size, p, len});
+    p += len;
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Again, please make sure this is supported by MSVC.

http://reviews.llvm.org/D4545