[PATCH] [ASan] Allow the users of SymbolizationLoop to make use of the -dsym_hint option in llvm-symbolizer

[Sergey Matveev]

================
Comment at: projects/compiler-rt/lib/asan/scripts/asan_symbolize.py:364
@@ +363,3 @@
+    #     |last_llvm_symbolizer|);
+    #  2. otherwise check if we've seen this hint already; if so,
+    #     reuse |last_llvm_symbolizer| which has the full set of hints;
----------------
s/this hint/all of the hints for this binary/

================
Comment at: projects/compiler-rt/lib/asan/scripts/asan_symbolize.py:371
@@ +370,3 @@
+      if self.system == 'Darwin' and self.dsym_hint_producer:
+        dsym_hints = self.dsym_hint_producer(binary)
+        for dsym_hint in dsym_hints:
----------------
Whoa whoa, let's tune the C++ down a bit :P

```
dsym_hints = set(self.dsym_hint_producer(binary))
use_last_symbolizer = bool(dsym_hints - self.dsym_hints)
self.dsym_hints |= dsym_hints
```

Also I suggest to rename this to dsym_hints_for_binary.

http://reviews.llvm.org/D6310