Enable unit tests for some utils in postsubmit

Enabled unit tests for hevcUtils, ExtractorFactory and TimedText in
postsubmit.

These were marked as dynamic-presubmit and those are now
changed to postsubmit as these tests now use DynamicConfig.xml and
can download the required files without any extra arguments.

After some time of running these in postsubmit, these will be changed
to presubmit.

Bug: 304383609
Test: atest ExtractorFactoryTest HEVCUtilsUnitTest TimedTextUnitTest
Change-Id: I934849f82062eac04f4fb988c1bf200fb434d815
diff --git a/media/libstagefright/TEST_MAPPING b/media/libstagefright/TEST_MAPPING
index 22885c9..5dd8423 100644
--- a/media/libstagefright/TEST_MAPPING
+++ b/media/libstagefright/TEST_MAPPING
@@ -1,8 +1,5 @@
 {
-  // tests which require dynamic content
-  // invoke with: atest -- --enable-module-dynamic-download=true
-  // TODO(b/148094059): unit tests not allowed to download content
-  "dynamic-presubmit": [
+  "postsubmit": [
     // writerTest fails about 5 out of 66
     // { "name": "writerTest" },
 
diff --git a/media/libstagefright/timedtext/TEST_MAPPING b/media/libstagefright/timedtext/TEST_MAPPING
index 35a5b11..f011d04 100644
--- a/media/libstagefright/timedtext/TEST_MAPPING
+++ b/media/libstagefright/timedtext/TEST_MAPPING
@@ -1,9 +1,5 @@
-// mappings for frameworks/av/media/libstagefright/timedtext
 {
-  // tests which require dynamic content
-  // invoke with: atest -- --enable-module-dynamic-download=true
-  // TODO(b/148094059): unit tests not allowed to download content
-  "dynamic-presubmit": [
+  "postsubmit": [
     { "name": "TimedTextUnitTest" }
   ]
 }