Permissions XML file for java_sdk_library is mutated for APEX

This change fixes a regression that was introduced with
I597bccbb177b6b6320c3a3edeff467243230d384. With the change, the content
of the permissions XML file for a java_sdk_library was determined before
the java_sdk_library is mutated for an APEX. As a result, the file path
to the implementation jar library was always set to
/system/framework/*.jar regardless of whether the java_sdk_library is
part of an APEX or not.

This change fixes the problem, by creating the permissions XML file via
a new module type. The content of the xml file is determined after the
xml file is mutated for APEXes.

Bug: 149600642
Test: m

Change-Id: Id21f8d8285df49b0b3be1daf0f101f2bc978eeb0
diff --git a/apex/apex.go b/apex/apex.go
index 54a335a..84043a5 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -2111,13 +2111,6 @@
 						return false
 					}
 					filesInfo = append(filesInfo, af)
-
-					pf := sdkLib.XmlPermissionsFile()
-					if pf == nil {
-						ctx.PropertyErrorf("java_libs", "%q failed to generate permission XML", depName)
-						return false
-					}
-					filesInfo = append(filesInfo, newApexFile(ctx, pf, pf.Base(), "etc/permissions", etc, nil))
 					return true // track transitive dependencies
 				} else {
 					ctx.PropertyErrorf("java_libs", "%q of type %q is not supported", depName, ctx.OtherModuleType(child))
@@ -2230,6 +2223,10 @@
 					}
 				} else if java.IsJniDepTag(depTag) {
 					return true
+				} else if java.IsXmlPermissionsFileDepTag(depTag) {
+					if prebuilt, ok := child.(android.PrebuiltEtcModule); ok {
+						filesInfo = append(filesInfo, apexFileForPrebuiltEtc(ctx, prebuilt, depName))
+					}
 				} else if am.CanHaveApexVariants() && am.IsInstallableToApex() {
 					ctx.ModuleErrorf("unexpected tag %q for indirect dependency %q", depTag, depName)
 				}