Add global C flags to compile_commands

This solves linter warnings in editor by adding flags to ignore errors
we don't care about. This also means that compile_commands.json is
closer to the flags we actually use for compilation.

Test: Checked generated compile_commands for new flags.

Change-Id: Id583da6eb5151a9baa9a47771f5f937c88bc43f7
diff --git a/cc/cc.go b/cc/cc.go
index 90185ea..40e40e9 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -215,7 +215,8 @@
 	// Local flags (which individual modules are responsible for). These may override global flags.
 	Local LocalOrGlobalFlags
 	// Global flags (which build system or toolchain is responsible for).
-	Global LocalOrGlobalFlags
+	Global          LocalOrGlobalFlags
+	NoOverrideFlags []string // Flags applied to the end of list of flags so they are not overridden
 
 	aidlFlags     []string // Flags that apply to aidl source files
 	rsFlags       []string // Flags that apply to renderscript source files