[PATCH] [Driver] Move description of toolchain specific include directories from the common driver code to the corresponding `MultilibSet` declarations

[Rafael Ávila de Espíndola]

The code change seems reasonable if the flexibility of a callback is needed. I have no opinion on whether it is.

Do you have the followup change where this is used?

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Comment at: include/clang/Driver/Multilib.h:158
@@ -152,1 +157,3 @@
 
+  MultilibSet &includeDirsCallback(IncludeDirsFunc F) {
+    IncludeCallback = F;
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setincludeDirsCallback would be the correct name, no?

http://reviews.llvm.org/D4720