Dedup generating xml file for java_sdk_library

Permission XML file for java_sdk_library is generated by
java_sdk_library itself now.

And, build rule is switched to android.WriteFile since "echo -e" is
not supported from build server. (-e is printed to output)

Bug: 145474221
Test: m com.android.cronet and check its permissions xml file
     also, m org.chromium.net.cronet.xml (created dynamically)
Change-Id: Iffb119151c49bc4fe6c4386fa267cca193f37dbc
diff --git a/apex/apex_test.go b/apex/apex_test.go
index 97600b6..a16e317 100644
--- a/apex/apex_test.go
+++ b/apex/apex_test.go
@@ -3288,8 +3288,8 @@
 		"etc/permissions/foo.xml",
 	})
 	// Permission XML should point to the activated path of impl jar of java_sdk_library
-	genXMLCommand := ctx.ModuleForTests("foo", "android_common_myapex").Output("foo.xml").RuleParams.Command
-	ensureContains(t, genXMLCommand, `<library name="foo" file="/apex/myapex/javalib/foo.jar"`)
+	xml := ctx.ModuleForTests("foo", "android_common_myapex").Output("foo.xml")
+	ensureContains(t, xml.Args["content"], `<library name="foo" file="/apex/myapex/javalib/foo.jar"`)
 }
 
 func TestRejectNonInstallableJavaLibrary(t *testing.T) {