[Keyboard Manager] Fixed app-specific shortcut causing app to lose focus scenario (#4902)

* Fixed focus issue and added tests

* Changed key names

* Use constant instead of hardcoded empty string

src/modules/keyboardmanager/common/KeyboardManagerConstants.h

@@ -96,4 +96,7 @@ namespace KeyboardManagerConstants
 
     // String constant for the default app name in Remap shortcuts
     inline const std::wstring DefaultAppName = L"All Apps";
+    
+    // String constant to represent no activated application in app-specific shortcuts
+    inline const std::wstring NoActivatedApp = L"";
 }

src/modules/keyboardmanager/common/KeyboardManagerState.cpp

@@ -528,4 +528,16 @@ std::wstring KeyboardManagerState::GetCurrentConfigName()
 {
     std::lock_guard<std::mutex> lock(currentConfig_mutex);
     return currentConfig;
-}
+}
+
+// Sets the activated target application in app-specfic shortcut
+void KeyboardManagerState::SetActivatedApp(const std::wstring& appName)
+{
+    activatedAppSpecificShortcutTarget = appName;
+}
+
+// Gets the activated target application in app-specfic shortcut
+std::wstring KeyboardManagerState::GetActivatedApp()
+{
+    return activatedAppSpecificShortcutTarget;
+}

src/modules/keyboardmanager/common/KeyboardManagerState.h

@@ -71,6 +71,9 @@ private:
     std::map<DWORD, std::unique_ptr<KeyDelay>> keyDelays;
     std::mutex keyDelays_mutex;
 
+    // Stores the activated target application in app-specfic shortcut
+    std::wstring activatedAppSpecificShortcutTarget;
+
     // Display a key by appending a border Control as a child of the panel.
     void AddKeyToLayout(const StackPanel& panel, const winrt::hstring& key);
 
@@ -190,4 +193,10 @@ public:
 
     // Gets the Current Active Configuration Name.
     std::wstring GetCurrentConfigName();
+
+    // Sets the activated target application in app-specfic shortcut
+    void SetActivatedApp(const std::wstring& appName);
+
+    // Gets the activated target application in app-specfic shortcut
+    std::wstring GetActivatedApp();
 };