IDE: preserve the environment in the triple

Adjust the triple manipulation to preserve the environment.  This is
particularly important for android which is an environment for Linux,
and Windows, where we support specific environments only.

lib/IDE/Utils.cpp

@@ -227,6 +227,8 @@ static std::string adjustClangTriple(StringRef TripleStr) {
     break;
   }
   OS << '-' << Triple.getVendorName() << '-' << Triple.getOSName();
+  if (Triple.hasEnvironment())
+    OS << '-' << Triple.getEnvironmentName();
   OS.flush();
   return Result;
 }