[android] Update to LTS NDK 27c

Add a new bits/ header to the Android overlay, include runtime libraries that are
auto-extracted and listed many times to the list of libraries to be de-duplicated,
enable a C++ interop test that's working again, and update the doc with new
libraries that need to be available to run a simple executable.

lib/DriverTool/autolink_extract_main.cpp

@@ -231,8 +231,11 @@ int autolink_extract_main(ArrayRef<const char *> Args, const char *Argv0,
       "-lswiftRegexBuilder",
       "-lswift_RegexParser",
       "-lswift_Backtracing",
+      "-lswift_Builtin_float",
+      "-lswift_math",
       "-lswiftSynchronization",
       "-lswiftGlibc",
+      "-lswiftAndroid",
       "-lBlocksRuntime",
       // Dispatch-specific Swift runtime libs
       "-ldispatch",