Add return statement to LinuxCapabilityToKernelValue.

sandbox/linux/services/credentials.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sandbox/linux/services/credentials.h"
 
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
 #include <sys/syscall.h>
@@ skipping 102 matching lines @@
 // Converts a LinuxCapability to the corresponding Linux CAP_XXX value.
 int LinuxCapabilityToKernelValue(LinuxCapability cap) {
   switch (cap) {
     case LinuxCapability::kCapSysChroot:
       return CAP_SYS_CHROOT;
     case LinuxCapability::kCapSysAdmin:
       return CAP_SYS_ADMIN;
   }
 
   LOG(FATAL) << "Invalid LinuxCapability: " << static_cast<int>(cap);
+  return 0;
 }
 
 }  // namespace.
 
 bool Credentials::DropAllCapabilities(int proc_fd) {
   if (!SetCapabilities(proc_fd, std::vector<LinuxCapability>())) {
     return false;
   }
 
   CHECK(!HasAnyCapability());
@@ skipping 141 matching lines @@
   CHECK_LE(0, proc_fd);
 
   CHECK(ChrootToSafeEmptyDir());
   CHECK(!base::DirectoryExists(base::FilePath("/proc")));
   CHECK(!ProcUtil::HasOpenDirectory(proc_fd));
   // We never let this function fail.
   return true;
 }
 
 }  // namespace sandbox.