aconfig: modify and filter flags before passing into java codegen

Before this change java codegen filter flags for exported mode in the
template. This change move the filter process to commands as other
codegen. Thus the codegen code will only generate code based on the
passed in flags.

Bug: 311152507
Test: atest aconfig.test aconfig.test.java AconfigJavaHostTest
Change-Id: I74045709cde19e6c687c3eb0d94050ea40cf5042

tools/aconfig/templates/FakeFeatureFlagsImpl.java.template

@@ -12,23 +12,11 @@ public class FakeFeatureFlagsImpl implements FeatureFlags \{
     }
 
 {{ for item in flag_elements}}
-{{ if library_exported }}
-
-{{ if item.exported }}
     @Override
     @UnsupportedAppUsage
     public boolean {item.method_name}() \{
         return getValue(Flags.FLAG_{item.flag_name_constant_suffix});
     }
-{{ endif }}
-
-{{ else }}
-    @Override
-    @UnsupportedAppUsage
-    public boolean {item.method_name}() \{
-        return getValue(Flags.FLAG_{item.flag_name_constant_suffix});
-    }
-{{ endif }}
 {{ endfor}}
     public void setFlag(String flagName, boolean value) \{
         if (!this.mFlagMap.containsKey(flagName)) \{
@@ -52,20 +40,11 @@ public class FakeFeatureFlagsImpl implements FeatureFlags \{
     }
 
     private Map<String, Boolean> mFlagMap = new HashMap<>(
-        {{ if library_exported }}
-        Map.ofEntries(
-            {{-for item in exported_flag_elements}}
-            Map.entry(Flags.FLAG_{item.flag_name_constant_suffix}, false)
-            {{ -if not @last }},{{ endif }}
-            {{ -endfor }}
-        )
-        {{ else }}
         Map.ofEntries(
             {{-for item in flag_elements}}
             Map.entry(Flags.FLAG_{item.flag_name_constant_suffix}, false)
             {{ -if not @last }},{{ endif }}
             {{ -endfor }}
         )
-        {{ endif }}
     );
 }