NaCl: Permit using the debug exception handler when the debug stub is enabled

This is in preparation for a NaCl-side change to make the debug stub
use the Windows debug exception handler process instead of Vectored
Exception Handling.

BUG=http://code.google.com/p/nativeclient/issues/detail?id=2948
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10836197

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@151171 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/nacl_host/nacl_process_host.cc

@@ -128,6 +128,7 @@ NaClProcessHost::NaClProcessHost(const GURL& manifest_url, bool off_the_record)
       internal_(new NaClInternal()),
       ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)),
       enable_exception_handling_(false),
+      enable_debug_stub_(false),
       off_the_record_(off_the_record) {
   process_.reset(content::BrowserChildProcessHost::Create(
       content::PROCESS_TYPE_NACL_LOADER, this));
@@ -145,6 +146,8 @@ NaClProcessHost::NaClProcessHost(const GURL& manifest_url, bool off_the_record)
       getenv("NACL_UNTRUSTED_EXCEPTION_HANDLING") != NULL) {
     enable_exception_handling_ = true;
   }
+  enable_debug_stub_ = CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kEnableNaClDebug);
 
   enable_ipc_proxy_ = CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableNaClIPCProxy);
@@ -622,8 +625,7 @@ bool NaClProcessHost::StartNaClExecution() {
   params.validation_cache_key = nacl_browser->GetValidationCacheKey();
   params.version = chrome::VersionInfo().CreateVersionString();
   params.enable_exception_handling = enable_exception_handling_;
-  params.enable_debug_stub =
-      CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableNaClDebug);
+  params.enable_debug_stub = enable_debug_stub_;
   params.enable_ipc_proxy = enable_ipc_proxy_;
 
   base::PlatformFile irt_file = nacl_browser->IrtFile();
@@ -735,9 +737,9 @@ void NaClProcessHost::OnAttachDebugExceptionHandler(const std::string& info,
 
 bool NaClProcessHost::AttachDebugExceptionHandler(const std::string& info,
                                                   IPC::Message* reply_msg) {
-  if (!enable_exception_handling_) {
+  if (!enable_exception_handling_ && !enable_debug_stub_) {
     DLOG(ERROR) <<
-        "Exception handling requested by NaCl process when not enabled";
+        "Debug exception handler requested by NaCl process when not enabled";
     return false;
   }
   if (debug_exception_handler_requested_) {

chrome/browser/nacl_host/nacl_process_host.h

@@ -153,6 +153,7 @@ class NaClProcessHost : public content::BrowserChildProcessHostDelegate {
   scoped_ptr<content::BrowserChildProcessHost> process_;
 
   bool enable_exception_handling_;
+  bool enable_debug_stub_;
 
   bool off_the_record_;