Set -fsjlj-exceptions for all 32-bit Windows compiles

Bug: http://b/116784799

Previously this was set only when stl was requested.  We can now pass
this for all C++ compilations.

Test: go/android-llvm-windows-testing
Change-Id: I43e635ff50d0f1a5e000f13021506aeece368b4a
diff --git a/cc/config/x86_windows_host.go b/cc/config/x86_windows_host.go
index cd0a508..b5b5553 100644
--- a/cc/config/x86_windows_host.go
+++ b/cc/config/x86_windows_host.go
@@ -49,7 +49,11 @@
 
 	windowsClangCppflags = []string{}
 
-	windowsX86ClangCppflags = []string{}
+	windowsX86ClangCppflags = []string{
+		// Use SjLj exceptions for 32-bit.  libgcc_eh implements SjLj
+		// exception model for 32-bit.
+		"-fsjlj-exceptions",
+	}
 
 	windowsX8664ClangCppflags = []string{}