cronet: remove sources on tm-mainline-prod

external/cronet does not exist yet on tm-mainline-prod.

Test: TH
Merged-In: Ie875e4108a0b2a82e9615d1f32f3b0bf76572146
Change-Id: I24fe26595e48713a277570877f02b64678ec9f9b

Tethering/common/TetheringLib/Android.bp

@@ -32,7 +32,7 @@ cronet_java_prejarjar_defaults = "CronetJavaPrejarjarDefaultsDisabled"
 // cronet_java_defaults_enabled_srcs is used to specify the srcs of CronetJavaDefaultsEnabled
 // This is required until the external/cronet is auto-merged to tm-mainline-prod and
 // :cronet_aml_api_sources is available
-cronet_java_defaults_enabled_srcs = [":cronet_aml_api_sources"]
+cronet_java_defaults_enabled_srcs = []
 // This is a placeholder comment to avoid merge conflicts
 // as cronet_defaults may have different values
 // depending on the branch