Create a singleton all_apex_contributions module type

This will be a container for the the apex_contributions
selected using build flags. This module will be used to query the state of
selected apex contributions instead of a global that can be mutated by
anyone.

It will set a provider containing metadata for source vs prebuilts
selection. To reduce the overhead of a new mutator, this will be done in
the existing `prebuilt_select` mutator.

It will validate that there are no dups (`foo` and `prebuilt_foo` cannot
be both selected)

Bug: 308174923

Test: go test ./android

Change-Id: Ie42999a71f35d70e0e977f5ab07ce451608d9f35
diff --git a/android/config.go b/android/config.go
index 4c31bb0..696632a 100644
--- a/android/config.go
+++ b/android/config.go
@@ -2129,3 +2129,41 @@
 	val, ok := c.productVariables.BuildFlags[name]
 	return val, ok
 }
+
+var (
+	mainlineApexContributionBuildFlags = []string{
+		"RELEASE_APEX_CONTRIBUTIONS_ADSERVICES",
+		"RELEASE_APEX_CONTRIBUTIONS_APPSEARCH",
+		"RELEASE_APEX_CONTRIBUTIONS_ART",
+		"RELEASE_APEX_CONTRIBUTIONS_BLUETOOTH",
+		"RELEASE_APEX_CONTRIBUTIONS_CONFIGINFRASTRUCTURE",
+		"RELEASE_APEX_CONTRIBUTIONS_CONNECTIVITY",
+		"RELEASE_APEX_CONTRIBUTIONS_CONSCRYPT",
+		"RELEASE_APEX_CONTRIBUTIONS_CRASHRECOVERY",
+		"RELEASE_APEX_CONTRIBUTIONS_DEVICELOCK",
+		"RELEASE_APEX_CONTRIBUTIONS_HEALTHFITNESS",
+		"RELEASE_APEX_CONTRIBUTIONS_IPSEC",
+		"RELEASE_APEX_CONTRIBUTIONS_MEDIA",
+		"RELEASE_APEX_CONTRIBUTIONS_MEDIAPROVIDER",
+		"RELEASE_APEX_CONTRIBUTIONS_ONDEVICEPERSONALIZATION",
+		"RELEASE_APEX_CONTRIBUTIONS_PERMISSION",
+		"RELEASE_APEX_CONTRIBUTIONS_REMOTEKEYPROVISIONING",
+		"RELEASE_APEX_CONTRIBUTIONS_SCHEDULING",
+		"RELEASE_APEX_CONTRIBUTIONS_SDKEXTENSIONS",
+		"RELEASE_APEX_CONTRIBUTIONS_STATSD",
+		"RELEASE_APEX_CONTRIBUTIONS_UWB",
+		"RELEASE_APEX_CONTRIBUTIONS_WIFI",
+	}
+)
+
+// Returns the list of _selected_ apex_contributions
+// Each mainline module will have one entry in the list
+func (c *config) AllApexContributions() []string {
+	ret := []string{}
+	for _, f := range mainlineApexContributionBuildFlags {
+		if val, exists := c.GetBuildFlag(f); exists && val != "" {
+			ret = append(ret, val)
+		}
+	}
+	return ret
+}