Revert "Revert "Turn off extern templates for most uses.""

This reverts commit 98c4e404ca.

Bug: http://b/25560311
Change-Id: Ied8afaf8f7cf29e74e521de5170e4ff30144f546

include/__config

@@ -649,7 +649,7 @@ template <unsigned> struct __static_assert_check {};
 #endif
 
 #ifndef _LIBCPP_EXTERN_TEMPLATE
-#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
+#define _LIBCPP_EXTERN_TEMPLATE(...)
 #endif
 
 #ifndef _LIBCPP_EXTERN_TEMPLATE2

src/algorithm.cpp

@@ -7,6 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#undef _LIBCPP_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
 #include "algorithm"
 #include "random"
 #include "mutex"

src/ios.cpp

@@ -9,6 +9,9 @@
 
 #include "__config"
 
+#undef _LIBCPP_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
+
 #include "ios"
 
 #include <stdlib.h>

src/locale.cpp

@@ -7,6 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#undef _LIBCPP_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
+
 // On Solaris, we need to define something to make the C99 parts of localeconv
 // visible.
 #ifdef __sun__

src/string.cpp

@@ -7,6 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#undef _LIBCPP_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
+
 #include "string"
 #include "cstdlib"
 #include "cwchar"

src/valarray.cpp

@@ -7,6 +7,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+#undef _LIBCPP_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
+
 #include "valarray"
 
 _LIBCPP_BEGIN_NAMESPACE_STD