Make a metaprogramming hack more C++11-compatible

Make a metaprogramming hack more C++11-compatible 

This is a refined version of https://codereview.chromium.org/13824006/ by @thakis which was reverted due to compilation errors on Windows.

Some classes have private "operator delete"s, which causes their 
destructors to be deleted in C++11. Clang's r178563 implemented 
this rule better, and as a result using these classes with memory 
instrumentation causes a compile error. To unblock the clang roll, 
give the metaprogramming helper class an explicit nondeleted 
destructor. (This is just a workaround, not a permanent fix, see bug.) 

See also http://lists.cs.uiuc.edu/pipermail/cfe-commits/Week-of-Mon-20130415/078311.html 

TBR=thakis
BUG=233473
TEST=Stuff still builds in C++11 mode after the next clang roll.

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=148715

[loislo, 2013-04-19 09:57:49]

lgtm

[yurys, 2013-04-19 10:05:57]

Committed patchset #1 manually as r148715 (presubmit successful).