ARC4RANDOM_EXPORT is defined as extern. Fixes issues in arc4random and libevent.
Solaris specific changes, will not send upstream.

--- a/ipc/chromium/src/third_party/libevent/arc4random.c    2016-03-01 09:29:36.602447178 -0800
+++ b/ipc/chromium/src/third_party/libevent/arc4random.c    2016-03-01 10:17:51.627857034 -0800
@@ -445,8 +445,8 @@ arc4random_stir(void)
 #endif

 #ifndef ARC4RANDOM_NOADDRANDOM
-ARC4RANDOM_EXPORT void
-arc4random_addrandom(const unsigned char *dat, int datlen)
+extern void
+arc4random_addrandom(uchar_t *dat, size_t datlen)
 {
        int j;
        _ARC4_LOCK();
@@ -477,7 +477,7 @@ arc4random(void)
 }
 #endif

-ARC4RANDOM_EXPORT void
+extern void
 arc4random_buf(void *_buf, size_t n)
 {
        unsigned char *buf = _buf;
--- a/config/system-headers	2015-11-03 11:34:17.000000000 +0100
+++ b/config/system-headers	2015-11-09 03:34:24.577525000 +0100
@@ -1064,7 +1064,6 @@
 sys/stat.h
 sys/statvfs.h
 sys/syscall.h
-sys/sysctl.h
 sys/sysinfo.h
 sys/sysmp.h
 sys/syssgi.h
--- a/ipc/chromium/src/third_party/libevent/arc4random.c	2016-03-23 11:47:53.743867536 -0700
+++ b/ipc/chromium/src/third_party/libevent/arc4random.c	2016-03-23 11:48:38.956865864 -0700
@@ -41,6 +41,10 @@
  * RC4 is a registered trademark of RSA Laboratories.
  */
 
+#if defined (OS_SOLARIS)
+#undef _EVENT_HAVE_SYS_SYSCTL_H
+#endif
+
 #ifndef ARC4RANDOM_EXPORT
 #define ARC4RANDOM_EXPORT
 #endif
@@ -59,7 +61,7 @@
 #include <sys/param.h>
 #include <sys/time.h>
 #ifdef _EVENT_HAVE_SYS_SYSCTL_H
-#include <sys/sysctl.h>
+;//#include <sys/sysctl.h>
 #endif
 #endif
 #include <limits.h>
--- a/ipc/chromium/moz.build	2016-03-28 13:41:06.878922929 -0700
+++ b/ipc/chromium/moz.build	2016-03-28 13:42:04.555448660 -0700
@@ -161,6 +161,23 @@ if os_bsd or os_linux:
             'src/base/message_pump_qt.cc',
         ]
 
+if os_solaris:
+    SOURCES += [
+	'src/base/atomicops_internals_x86_gcc.cc',
+	'src/base/idle_timer_none.cc',
+	'src/base/process_util_linux.cc',
+	'src/base/time_posix.cc',
+    ]
+    if CONFIG['MOZ_WIDGET_GTK']:
+	SOURCES += [
+            'src/base/message_pump_glib.cc',
+	]
+    if not CONFIG['MOZ_NATIVE_LIBEVENT']:
+	SOURCES += [
+            'src/third_party/libevent/devpoll.c',
+	]
+    LOCAL_INCLUDES += ['src/third_party/libevent/solaris']
+
 ost = CONFIG['OS_TEST']
 if '86' not in ost and 'arm' not in ost and 'mips' not in ost:
     SOURCES += [
diff a/ipc/chromium/src/third_party/libeventcommon.mozbuild b/ipc/chromium/src/third_party/libeventcommon.mozbuild
--- a/ipc/chromium/src/third_party/libeventcommon.mozbuild	2015-11-03 11:34:14.000000000 +0100
+++ b/ipc/chromium/src/third_party/libeventcommon.mozbuild	2015-11-09 03:34:24.579311000 +0100
@@ -9,6 +9,7 @@
 os_openbsd = 0
 os_bsd = 0
 os_linux = 0
+os_solaris = 0
 
 if CONFIG['OS_ARCH'] == 'WINNT':
     os_win = 1
@@ -21,6 +22,9 @@ else:
                                'NetBSD', 'OpenBSD']:
         os_bsd = 1
         libevent_include_suffix = 'bsd'
+    elif CONFIG['OS_ARCH'] == 'SunOS':
+        os_solaris = 1
+        libevent_include_suffix = 'solaris'
     else:
         os_linux = 1
         if CONFIG['OS_TARGET'] == 'Android':
diff a/ipc/chromium/src/third_party/libevent/event.c b/ipc/chromium/src/third_party/libevent/event.c
--- a/ipc/chromium/src/third_party/libevent/event.c	2015-11-03 11:34:14.000000000 +0100
+++ b/ipc/chromium/src/third_party/libevent/event.c	2015-11-09 03:34:24.485030000 +0100
@@ -70,7 +70,7 @@
 #include "util-internal.h"
 
 #ifdef _EVENT_HAVE_EVENT_PORTS
-extern const struct eventop evportops;
+//extern const struct eventop evportops;
 #endif
 #ifdef _EVENT_HAVE_SELECT
 extern const struct eventop selectops;
@@ -79,7 +79,7 @@ extern const struct eventop selectops;
 extern const struct eventop pollops;
 #endif
 #ifdef _EVENT_HAVE_EPOLL
-extern const struct eventop epollops;
+//extern const struct eventop epollops;
 #endif
 #ifdef _EVENT_HAVE_WORKING_KQUEUE
 extern const struct eventop kqops;
@@ -94,13 +94,13 @@ extern const struct eventop win32ops;
 /* Array of backends in order of preference. */
 static const struct eventop *eventops[] = {
 #ifdef _EVENT_HAVE_EVENT_PORTS
-	&evportops,
+	//&evportops,
 #endif
 #ifdef _EVENT_HAVE_WORKING_KQUEUE
 	&kqops,
 #endif
 #ifdef _EVENT_HAVE_EPOLL
-	&epollops,
+	//&epollops,
 #endif
 #ifdef _EVENT_HAVE_DEVPOLL
 	&devpollops,
@@ -2883,8 +2883,8 @@
 #endif
 	if (evsig_global_setup_locks_(enable_locks) < 0)
 		return -1;
-	if (evutil_secure_rng_global_setup_locks_(enable_locks) < 0)
-		return -1;
+//	if (evutil_secure_rng_global_setup_locks_(enable_locks) < 0)
+//		return -1;
 	return 0;
 }
 #endif