Add BUILD_BROKEN_USES_NETWORK

Some people apparently still talk to the network during their build.
Allow this temporarily with a BUILD_BROKEN_USES_NETWORK check.

Bug: 129992021
Test: attempt to talk to the network during the build with and without
      this flag.
Change-Id: Ifb967c656aa24c4599e7232d0f1b5a303b5bac52
diff --git a/ui/build/config.go b/ui/build/config.go
index 64270f8..7eb3a72 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -55,6 +55,7 @@
 
 	brokenDupRules     bool
 	brokenPhonyTargets bool
+	brokenUsesNetwork  bool
 
 	pathReplaced bool
 }
@@ -622,6 +623,14 @@
 	return c.brokenPhonyTargets
 }
 
+func (c *configImpl) SetBuildBrokenUsesNetwork(val bool) {
+	c.brokenUsesNetwork = val
+}
+
+func (c *configImpl) BuildBrokenUsesNetwork() bool {
+	return c.brokenUsesNetwork
+}
+
 func (c *configImpl) SetTargetDeviceDir(dir string) {
 	c.targetDeviceDir = dir
 }