Reland: Move the Once cache for dexpreopt.GlobalConfig into the
dexpreopt package.

Preparation for a future CL that will need to get the make-written
GlobalConfig from within dexpreopt.

Also rename the Load*Config functions to Parse*Config, since they don't
actually load the config files anymore.

This relands https://r.android.com/1211982.

Bug: 145934348
Test: m
Change-Id: Icb9332a93811d77d2d8b06e983b92501b180a358
diff --git a/java/java_test.go b/java/java_test.go
index 9c5680b..129b17b 100644
--- a/java/java_test.go
+++ b/java/java_test.go
@@ -99,7 +99,7 @@
 	t.Helper()
 
 	pathCtx := android.PathContextForTesting(config)
-	setDexpreoptTestGlobalConfig(config, dexpreopt.GlobalConfigForTests(pathCtx))
+	dexpreopt.SetTestGlobalConfig(config, dexpreopt.GlobalConfigForTests(pathCtx))
 
 	ctx.Register(config)
 	_, errs := ctx.ParseBlueprintsFiles("Android.bp")
@@ -118,7 +118,7 @@
 	ctx := testContext()
 
 	pathCtx := android.PathContextForTesting(config)
-	setDexpreoptTestGlobalConfig(config, dexpreopt.GlobalConfigForTests(pathCtx))
+	dexpreopt.SetTestGlobalConfig(config, dexpreopt.GlobalConfigForTests(pathCtx))
 
 	ctx.Register(config)
 	_, errs := ctx.ParseBlueprintsFiles("Android.bp")