Updates stlport's cmath to provide isfinite, isinf, isnan and signbit…

… as members of the std namespace

This is required by the latest WebKit which uses cmath and expects these
functions to be in the std namespace. We could modify WebKit to expect these
functions to be in the global namespace (as other platforms have done, see
JavaScriptCore/wtf/MathExtras.h). However, in the simulator build, these
functions are in the std namespace, as they should be. So the WebKit
modification would have to be dependent on the Android build type. Instead, it's
better to fix this in stlport.

The fix used to achieve this is copied from cmath from GNU C++ 4.2.

Change-Id: Ifdcecbf256b44c837adad370894d385198fe4603

stlport/stl/_cmath.h

@@ -531,6 +531,24 @@ _STLP_DEF_MATH_INLINE2(hypot, _hypot)
 #endif
 
 #if defined (_STLP_IMPORT_VENDOR_CSTD) && !defined (_STLP_NO_CSTD_FUNCTION_IMPORTS)
+#if defined (ANDROID)
+namespace __captured {
+template<typename _Tp> inline int __capture_isfinite(_Tp __f) { return isfinite(__f); }
+template<typename _Tp> inline int __capture_isinf(_Tp __f) { return isinf(__f); }
+template<typename _Tp> inline int __capture_isnan(_Tp __f) { return isnan(__f); }
+template<typename _Tp> inline int __capture_signbit(_Tp __f) { return signbit(__f); }
+}
+#undef isfinite
+#undef isinf
+#undef isnan
+#undef signbit
+namespace __captured {
+template<typename _Tp> inline int isfinite(_Tp __f) { return __capture_isfinite(__f); }
+template<typename _Tp> inline int isinf(_Tp __f) { return __capture_isinf(__f); }
+template<typename _Tp> inline int isnan(_Tp __f) { return __capture_isnan(__f); }
+template<typename _Tp> inline int signbit(_Tp __f) { return __capture_signbit(__f); }
+}
+#endif
 _STLP_BEGIN_NAMESPACE
 using ::abs;
 using ::acos;
@@ -555,11 +573,19 @@ using ::frexp;
 #if !(defined(__HP_aCC) && defined(_STLP_DEBUG))
 using ::hypot;
 #endif
+#if defined (ANDROID)
+using __captured::isfinite;
+using __captured::isinf;
+using __captured::isnan;
+#endif
 using ::ldexp;
 using ::log;
 using ::log10;
 using ::modf;
 using ::pow;
+#if defined (ANDROID)
+using __captured::signbit;
+#endif
 using ::sin;
 using ::sinh;
 using ::sqrt;