feat(clipboard-manager): implement `clear` on iOS and Android (#1462)

.changes/clear-clipboard.md

@@ -0,0 +1,5 @@
+---
+"clipboard-manager": "minor"
+---
+
+Add support for clearing clipboard text on iOS and Android. 

plugins/clipboard-manager/android/src/main/java/ClipboardPlugin.kt

@@ -92,7 +92,11 @@ class ClipboardPlugin(private val activity: Activity) : Plugin(activity) {
     val clipData = when (args) {
       is WriteOptions.PlainText -> {
         ClipData.newPlainText(args.label, args.text)
+      } else -> {
+        invoke.reject("Invalid write options provided")
+        return
       }
+
     }
 
     manager.setPrimaryClip(clipData)
@@ -120,4 +124,12 @@ class ClipboardPlugin(private val activity: Activity) : Plugin(activity) {
 
     invoke.resolveObject(data)
   }
+
+  @Command
+  fun clear(invoke: Invoke) {
+      if (manager.hasPrimaryClip()) {
+          manager.clearPrimaryClip()
+      }
+      invoke.resolve()
+  }
 }

plugins/clipboard-manager/ios/Sources/ClipboardPlugin.swift

@@ -38,6 +38,12 @@ class ClipboardPlugin: Plugin {
       invoke.reject("Clipboard is empty")
     }
   }
+    
+  @objc public func clear(_ invoke: Invoke) throws {
+      let clipboard = UIPasteboard.general
+      clipboard.items = []
+      invoke.resolve()
+    }
 }
 
 @_cdecl("init_plugin_clipboard")

plugins/clipboard-manager/src/mobile.rs

@@ -92,9 +92,7 @@ impl<R: Runtime> Clipboard<R> {
     }
 
     pub fn clear(&self) -> crate::Result<()> {
-        Err(crate::Error::Clipboard(
-            "Unsupported on this platform".to_string(),
-        ))
+        self.0.run_mobile_plugin("clear", ()).map_err(Into::into)
     }
 }