Exit cleanly for the SRPC "log" requests instead of generating crash reports.

src/shared/platform/nacl_log.c

Index: src/shared/platform/nacl_log.c
diff --git a/src/shared/platform/nacl_log.c b/src/shared/platform/nacl_log.c
index 2e6e4d1a7decf65aeb3fcca810b654230c2544e5..5f172a3eca9c7350e7a9948593cd65d45c91ca0d 100644
--- a/src/shared/platform/nacl_log.c
+++ b/src/shared/platform/nacl_log.c
@@ -352,8 +352,9 @@ void NaClLogUnlock(void) {
 #ifdef __COVERITY__
         NaClAbort();  /* help coverity figure out that this is the default */
 #else
-        (*gNaClLogAbortBehavior)();
+        NaClLogRunAbortBehavior();
 #endif
+        /* The abort behavior hook may not abort, so abort here in case. */
         NaClAbort();
       }
       break;
@@ -716,3 +717,7 @@ void NaClLogSetAbortBehavior(void (*fn)(void)) {
   gNaClLogAbortBehavior = fn;
   NaClXMutexUnlock(&log_mu);
 }
+
+void NaClLogRunAbortBehavior(void) {
+  (*gNaClLogAbortBehavior)();
+}