[Windows Sandbox] Turn on MITIGATION_EXTENSION_POINT_DISABLE for browser processes.

chrome_elf/chrome_elf_main.cc

Index: chrome_elf/chrome_elf_main.cc
diff --git a/chrome_elf/chrome_elf_main.cc b/chrome_elf/chrome_elf_main.cc
index e2b57aa56e34d6d911d29d8b1d9dea359507900c..46e6e15b794bb8e1cf76ef0eac76907df32e9ad2 100644
--- a/chrome_elf/chrome_elf_main.cc
+++ b/chrome_elf/chrome_elf_main.cc
@@ -16,6 +16,7 @@
 #include "chrome_elf/blacklist/blacklist.h"
 #include "chrome_elf/blacklist/crashpad_helper.h"
 #include "chrome_elf/chrome_elf_constants.h"
+#include "chrome_elf/chrome_elf_security.h"
 #include "components/crash/content/app/crashpad.h"
 #include "components/crash/core/common/crash_keys.h"
 
@@ -49,7 +50,6 @@ void InitializeCrashReportingForProcess() {
   ChromeCrashReporterClient::InitializeCrashReportingForProcess();
 }
 
-#if !defined(ADDRESS_SANITIZER)
 // chrome_elf loads early in the process and initializes Crashpad. That in turn
 // uses the SetUnhandledExceptionFilter API to set a top level exception
 // handler for the process. When the process eventually initializes, CRT sets
@@ -80,7 +80,6 @@ void DisableSetUnhandledExceptionFilter() {
       SetUnhandledExceptionFilterPatch);
   CHECK(patched == 0);
 }
-#endif // !defined(ADDRESS_SANITIZER)
 
 }  // namespace
 
@@ -113,13 +112,13 @@ BOOL APIENTRY DllMain(HMODULE module, DWORD reason, LPVOID reserved) {
     InitializeCrashReportingForProcess();
     // CRT on initialization installs an exception filter which calls
     // TerminateProcess. We need to hook CRT's attempt to set an exception
-    // handler and ignore it. Don't do this when ASan is present, or ASan will
-    // fail to install its own unhandled exception filter.
-#if !defined(ADDRESS_SANITIZER)
+    // handler and ignore it.
     DisableSetUnhandledExceptionFilter();
-#endif
 
     install_static::InitializeProcessType();
+    if (install_static::g_process_type ==
+        install_static::ProcessType::BROWSER_PROCESS)
+      EarlyBrowserSecurity();
 
     __try {
       blacklist::Initialize(false);  // Don't force, abort if beacon is present.