Fix stack overflow for mutual recursion.

There was an error where we would have a pc that was in the method
which generated the stack overflow. This didn't work however
because the stack overflow check was before we stored the method in
the stack. The result was that the stack overflow handler had a PC
which wasnt necessarily in the method at the top of the stack. This
is now fixed by always restoring the link register before branching
to the throw entrypoint.

Slight code size regression on ARM/Mips (unmeasured). Regression on ARM
is 4 bytes of code per stack overflow check. Some of this regression is
mitigated by having one less GC safepoint.

Also adds test case for StackOverflowError issue (from bdc).

Tests passing: ARM, X86, Mips
Phone booting: ARM

Bug: https://code.google.com/p/android/issues/detail?id=66411
Bug: 12967914
Change-Id: I96fe667799458b58d1f86671e051968f7be78d5d

(cherry-picked from c0f96d03a1855fda7d94332331b94860404874dd)
diff --git a/test/018-stack-overflow/src/Main.java b/test/018-stack-overflow/src/Main.java
index f79c269..41adabc 100644
--- a/test/018-stack-overflow/src/Main.java
+++ b/test/018-stack-overflow/src/Main.java
@@ -19,17 +19,46 @@
  */
 public class Main {
     public static void main(String args[]) {
+        testSelfRecursion();
+        testMutualRecursion();
+        System.out.println("SOE test done");
+    }
+
+    private static void testSelfRecursion() {
         try {
             stackOverflowTestSub(0.0, 0.0, 0.0);
         }
         catch (StackOverflowError soe) {
-            System.out.println("caught SOE");
+            System.out.println("caught SOE in testSelfRecursion");
         }
-        System.out.println("SOE test done");
     }
 
-    private static void stackOverflowTestSub(double pad1, double pad2,
-            double pad3) {
+    private static void stackOverflowTestSub(double pad1, double pad2, double pad3) {
         stackOverflowTestSub(pad1, pad2, pad3);
     }
+
+    private static void testMutualRecursion() {
+        try {
+            foo(0.0, 0.0, 0.0);
+        }
+        catch (StackOverflowError soe) {
+            System.out.println("caught SOE in testMutualRecursion");
+        }
+    }
+
+    private static void foo(double pad1, double pad2, double pad3) {
+        bar(pad1, pad2, pad3);
+    }
+
+    private static void bar(double pad1, double pad2, double pad3) {
+        baz(pad1, pad2, pad3);
+    }
+
+    private static void baz(double pad1, double pad2, double pad3) {
+        qux(pad1, pad2, pad3);
+    }
+
+    private static void qux(double pad1, double pad2, double pad3) {
+        foo(pad1, pad2, pad3);
+    }
 }