Write dexpreopt.config again during the build

Writing $OUT/dexpreopt.config during build setup and then using
it during the build causes bad incremental builds if a cleanspec
removes $OUT/dexpreopt.config.  Create a rule in Soong to write
out a copy so that it is a normal build artifact.

Bug: 132379813
Test: m checkbuild
Change-Id: I7755a7f8c1d6561fc83022a7f4cf7e4a64e989c9

java/dexpreopt_config.go

@@ -15,40 +15,50 @@
 package java
 
 import (
-	"android/soong/android"
-	"android/soong/dexpreopt"
 	"path/filepath"
 	"strings"
+
+	"android/soong/android"
+	"android/soong/dexpreopt"
 )
 
 // dexpreoptGlobalConfig returns the global dexpreopt.config.  It is loaded once the first time it is called for any
 // ctx.Config(), and returns the same data for all future calls with the same ctx.Config().  A value can be inserted
 // for tests using setDexpreoptTestGlobalConfig.
 func dexpreoptGlobalConfig(ctx android.PathContext) dexpreopt.GlobalConfig {
+	return dexpreoptGlobalConfigRaw(ctx).global
+}
+
+type globalConfigAndRaw struct {
+	global dexpreopt.GlobalConfig
+	data   []byte
+}
+
+func dexpreoptGlobalConfigRaw(ctx android.PathContext) globalConfigAndRaw {
 	return ctx.Config().Once(dexpreoptGlobalConfigKey, func() interface{} {
 		if f := ctx.Config().DexpreoptGlobalConfig(); f != "" {
 			ctx.AddNinjaFileDeps(f)
-			globalConfig, err := dexpreopt.LoadGlobalConfig(ctx, f)
+			globalConfig, data, err := dexpreopt.LoadGlobalConfig(ctx, f)
 			if err != nil {
 				panic(err)
 			}
-			return globalConfig
+			return globalConfigAndRaw{globalConfig, data}
 		}
 
 		// No global config filename set, see if there is a test config set
 		return ctx.Config().Once(dexpreoptTestGlobalConfigKey, func() interface{} {
 			// Nope, return a config with preopting disabled
-			return dexpreopt.GlobalConfig{
+			return globalConfigAndRaw{dexpreopt.GlobalConfig{
 				DisablePreopt: true,
-			}
+			}, nil}
 		})
-	}).(dexpreopt.GlobalConfig)
+	}).(globalConfigAndRaw)
 }
 
 // setDexpreoptTestGlobalConfig sets a GlobalConfig that future calls to dexpreoptGlobalConfig will return.  It must
 // be called before the first call to dexpreoptGlobalConfig for the config.
 func setDexpreoptTestGlobalConfig(config android.Config, globalConfig dexpreopt.GlobalConfig) {
-	config.Once(dexpreoptTestGlobalConfigKey, func() interface{} { return globalConfig })
+	config.Once(dexpreoptTestGlobalConfigKey, func() interface{} { return globalConfigAndRaw{globalConfig, nil} })
 }
 
 var dexpreoptGlobalConfigKey = android.NewOnceKey("DexpreoptGlobalConfig")