Merge "Provide some guidance for the confusing "does not provide a dex boot jar" message."

		dst := dstBootJarsByModule[name]

		if src == nil {

			// A dex boot jar should be provided by the source java module. It needs to be installable or

			// have compile_dex=true - cf. assignments to java.Module.dexJarFile.

			//

			// However, the source java module may be either replaced or overridden (using prefer:true) by

			// a prebuilt java module with the same name. In that case the dex boot jar needs to be

			// provided by the corresponding prebuilt APEX module. That APEX is the one that refers

			// through a exported_(boot|systemserver)classpath_fragments property to a

			// prebuilt_(boot|systemserver)classpath_fragment module, which in turn lists the prebuilt

			// java module in the contents property. If that chain is broken then this dependency will

			// fail.

			if !ctx.Config().AllowMissingDependencies() {

				ctx.ModuleErrorf("module %s does not provide a dex boot jar", name)

				ctx.ModuleErrorf("module %s does not provide a dex boot jar (see comment next to this message in Soong for details)", name)

			} else {

				ctx.AddMissingDependencies([]string{name})

			}