Prevent replacing missing dependency glob rules with errors

AndroidModuleContext.Build() replaces all build statements with errors
when the module has missing dependencies, but modules may try to create
glob rules to detect when missing dependencies have been satisified, and
those rules should not be replaced with errors.  Whitelist globRule
build statements.

Change-Id: I2a3cd53c05cea44cec9b5a99090d8778ca954d69
diff --git a/common/module.go b/common/module.go
index ee028da..f3f1263 100644
--- a/common/module.go
+++ b/common/module.go
@@ -440,7 +440,7 @@
 }
 
 func (a *androidModuleContext) Build(pctx blueprint.PackageContext, params blueprint.BuildParams) {
-	if a.missingDeps != nil {
+	if a.missingDeps != nil && params.Rule != globRule {
 		a.ninjaError(params.Outputs, fmt.Errorf("module %s missing dependencies: %s\n",
 			a.ModuleName(), strings.Join(a.missingDeps, ", ")))
 		return