Remove redundant setting of DistFiles by apexBundle

A previous change handles dist properties automatically for all module
types and as a result has made the apexBundle setting of DistFiles
redundant so this change removes that.

Test: m nothing
      m dist sdk - before and after this change, compare result to
      make sure that there are no significant differences.
      Test the effect on the apex by following instructions in
      http://b/172951145
Bug: 174226317
Change-Id: If6f741b5b73b3335f4c478a6528f5f311cd633e4

apex/apex.go

@@ -349,8 +349,6 @@ type apexBundle struct {
 	lintReports android.Paths
 
 	prebuiltFileToDelete string
-
-	distFiles android.TaggedDistFiles
 }
 
 // apexFileClass represents a type of file that can be included in APEX.
@@ -1799,7 +1797,6 @@ func (a *apexBundle) GenerateAndroidBuildActions(ctx android.ModuleContext) {
 	}
 	a.buildApexDependencyInfo(ctx)
 	a.buildLintReports(ctx)
-	a.distFiles = a.GenerateTaggedDistFiles(ctx)
 
 	// Append meta-files to the filesInfo list so that they are reflected in Android.mk as well.
 	if a.installable() {