Small cleanup in DeferredComponentManager.java‎ (#178585)

this change : 
- fixes the link in docs that is specified as a text
- removes `unnecessary` `public/abstract` modifiers in a `public
interface`

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---------

Co-authored-by: Matt Boetger <matt.boetger@gmail.com>
Co-authored-by: Matt Boetger <boetger@google.com>

Author: AbdeMohlbi

engine/src/flutter/shell/platform/android/io/flutter/embedding/engine/deferredcomponents/DeferredComponentManager.java

@@ -18,7 +18,8 @@
  *
  * <p>DeferredComponentManager handles the embedder/Android level tasks of downloading, installing,
  * and loading Dart deferred libraries. A typical code-flow begins with a Dart call to loadLibrary()
- * on deferred imported library. See https://dart.dev/guides/language/language-tour#deferred-loading
+ * on deferred imported library. See <a
+ * href="https://dart.dev/guides/language/language-tour#deferred-loading">https://dart.dev/guides/language/language-tour#deferred-loading</a>
  * This call retrieves a unique identifier called the loading unit id, which is assigned by
  * gen_snapshot during compilation. The loading unit id is passed down through the engine and
  * invokes installDeferredComponent. Once the component is downloaded, loadAssets and
@@ -45,7 +46,7 @@ public interface DeferredComponentManager {
    * is fully initialized, this method should be called to provide the FlutterJNI instance to use
    * for use in loadDartLibrary and loadAssets.
    */
-  public abstract void setJNI(FlutterJNI flutterJNI);
+  void setJNI(FlutterJNI flutterJNI);
 
   /**
    * Sets the DeferredComponentChannel system channel to handle the framework API to directly call
@@ -66,7 +67,7 @@ public interface DeferredComponentManager {
    * DeferredComponentChannel.completeInstallSuccess} while errors and failures should call {@link
    * DeferredComponentChannel.completeInstallError}.
    */
-  public abstract void setDeferredComponentChannel(DeferredComponentChannel channel);
+  void setDeferredComponentChannel(DeferredComponentChannel channel);
 
   /**
    * Request that the deferred component be downloaded and installed.
@@ -121,7 +122,7 @@ public interface DeferredComponentManager {
    *     an associated Dart deferred library, loading unit id should a negative value and
    *     componentName must be non-null.
    */
-  public abstract void installDeferredComponent(int loadingUnitId, String componentName);
+  void installDeferredComponent(int loadingUnitId, String componentName);
 
   /**
    * Gets the current state of the installation session corresponding to the specified loadingUnitId
@@ -156,7 +157,7 @@ public interface DeferredComponentManager {
    * @param loadingUnitId The unique identifier associated with a Dart deferred library.
    * @param componentName The deferred component name as defined in bundle_config.yaml.
    */
-  public abstract String getDeferredComponentInstallState(int loadingUnitId, String componentName);
+  String getDeferredComponentInstallState(int loadingUnitId, String componentName);
 
   /**
    * Extract and load any assets and resources from the deferred component for use by Flutter.
@@ -178,7 +179,7 @@ public interface DeferredComponentManager {
    * @param loadingUnitId The unique identifier associated with a Dart deferred library.
    * @param componentName The deferred component name as defined in bundle_config.yaml.
    */
-  public abstract void loadAssets(int loadingUnitId, String componentName);
+  void loadAssets(int loadingUnitId, String componentName);
 
   /**
    * Load the .so shared library file into the Dart VM.
@@ -205,7 +206,7 @@ public interface DeferredComponentManager {
    *     Play Store deferred component delivery, this name corresponds to the root name on the
    *     installed APKs in which to search for the desired shared library .so file.
    */
-  public abstract void loadDartLibrary(int loadingUnitId, String componentName);
+  void loadDartLibrary(int loadingUnitId, String componentName);
 
   /**
    * Request that the specified component be uninstalled.
@@ -229,10 +230,10 @@ public interface DeferredComponentManager {
    * @param loadingUnitId The unique identifier associated with a Dart deferred library.
    * @param componentName The deferred component name as defined in bundle_config.yaml.
    */
-  public abstract boolean uninstallDeferredComponent(int loadingUnitId, String componentName);
+  boolean uninstallDeferredComponent(int loadingUnitId, String componentName);
 
   /**
    * Cleans up and releases resources. This object is no longer usable after calling this method.
    */
-  public abstract void destroy();
+  void destroy();
 }