Small fixes for Android.

runtime/vm/signal_handler_android.cc

Index: runtime/vm/signal_handler_android.cc
===================================================================
--- runtime/vm/signal_handler_android.cc	(revision 35316)
+++ runtime/vm/signal_handler_android.cc	(working copy)
@@ -2,30 +2,60 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-#include "platform/thread.h"
 #include "vm/globals.h"
+#include "vm/simulator.h"
 #include "vm/signal_handler.h"
 #if defined(TARGET_OS_ANDROID)
 
 namespace dart {
 
 uintptr_t SignalHandler::GetProgramCounter(const mcontext_t& mcontext) {
+  uintptr_t pc = 0;
+
+#if defined(TARGET_ARCH_ARM)
+  pc = static_cast<uintptr_t>(mcontext.arm_pc);
+#else
   UNIMPLEMENTED();
+#endif  // TARGET_ARCH_...
+  return pc;
 }
 
 
 uintptr_t SignalHandler::GetFramePointer(const mcontext_t& mcontext) {
+  uintptr_t fp = 0;
+
+#if defined(TARGET_ARCH_ARM)
+  fp = static_cast<uintptr_t>(mcontext.arm_fp);
+#else
   UNIMPLEMENTED();
+#endif  // TARGET_ARCH_...
+
+  return fp;
 }
 
 
 uintptr_t SignalHandler::GetStackPointer(const mcontext_t& mcontext) {
+  uintptr_t sp = 0;
+
+#if defined(TARGET_ARCH_ARM)
+  sp = static_cast<uintptr_t>(mcontext.arm_sp);
+#else
   UNIMPLEMENTED();
+#endif  // TARGET_ARCH_...
+  return sp;
 }
 
 
 void SignalHandler::Install(SignalAction action) {
-  UNIMPLEMENTED();
+  struct sigaction act;
+  memset(&act, 0, sizeof(act));
+  act.sa_sigaction = action;
+  act.sa_flags = SA_RESTART | SA_SIGINFO;
+  sigemptyset(&act.sa_mask);
+  // TODO(johnmccutchan): Do we care about restoring the signal handler?
+  struct sigaction old_act;
+  int r = sigaction(SIGPROF, &act, &old_act);
+  ASSERT(r == 0);
 }