[Android] Roll to NDK r12b.

build/config/android/BUILD.gn

Index: build/config/android/BUILD.gn
diff --git a/build/config/android/BUILD.gn b/build/config/android/BUILD.gn
index 8343861ab103a02cec8cde5e940b3994a2098f62..9d535522d9ba4474cee7075eabddd482f5bd6875 100644
--- a/build/config/android/BUILD.gn
+++ b/build/config/android/BUILD.gn
@@ -121,6 +121,14 @@ config("runtime_library") {
   } else {
     libs = [ "c++_static" ]
   }
+  libs += [
+    "c++abi",

[agrieve, 2016/09/04 00:44:32]

Might need to update cpplib_* with these extra libs as well:
https://cs.chromium.org/chromium/src/build/android/BUILD.gn?q=c%5C%2B%5C%2B_s...

[jbudorick, 2016/09/05 16:33:03]

I don't think that's necessary here; libc++_shared is the only .so. Everything
else is a static library.

+    "android_support",
+  ]
+
+  if (current_cpu == "arm") {

[agrieve, 2016/09/04 00:44:32]

This raises an eyebrow (needs a comment). Why only on arm? Could this be moved
to the component(s) that require it?

[jbudorick, 2016/09/05 16:33:03]

Comment added. libc++ requires it, but only on arm.
https://chromium.googlesource.com/android_ndk/+/a0190968500138134251e1c0e264d...

+    libs += [ "unwind" ]
+  }
 
   # Manually link the libgcc.a that the cross compiler uses. This is
   # absolute because the linker will look inside the sysroot if it's not.