[CQ] De-duplicate color parsing and app creation code (#8082)

Clean up some code duplication in color parsing and Flutter app
creation.

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[test-exempt].
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Author: pq

flutter-idea/src/io/flutter/editor/FlutterColors.java

@@ -112,7 +112,7 @@ private static String maybeTrimSuffix(String value, String suffix) {
     return value;
   }
 
-  private static Color parseColor(String hexValue) {
+  static @Nullable Color parseColor(String hexValue) {
     if (hexValue == null) {
       return null;
     }

flutter-idea/src/io/flutter/editor/FlutterCupertinoColors.java

@@ -37,7 +37,7 @@ public class FlutterCupertinoColors {
     for (Map.Entry<Object, Object> entry : colors.entrySet()) {
       final String name = (String)entry.getKey();
       final String value = (String)entry.getValue();
-      final Color color = parseColor(value);
+      final Color color = FlutterColors.parseColor(value);
       if (color != null) {
         colorToName.put(color, name);
       }
@@ -90,25 +90,8 @@ private static String maybeTrimSuffix(String value, String suffix) {
     return value;
   }
 
-  private static Color parseColor(String hexValue) {
-    if (hexValue == null) {
-      return null;
-    }
-
-    try {
-      // argb to r, g, b, a
-      final long value = Long.parseLong(hexValue, 16);
-
-      //noinspection UseJBColor
-      return new Color((int)(value >> 16) & 0xFF, (int)(value >> 8) & 0xFF, (int)value & 0xFF, (int)(value >> 24) & 0xFF);
-    }
-    catch (IllegalArgumentException e) {
-      return null;
-    }
-  }
-
-  private static Color getColorValue(String name) {
+  private static @Nullable Color getColorValue(String name) {
     final String hexValue = colors.getProperty(name);
-    return parseColor(hexValue);
+    return FlutterColors.parseColor(hexValue);
   }
 }

flutter-idea/src/io/flutter/run/SdkAttachConfig.java

@@ -81,22 +81,7 @@ public LaunchState getState(@NotNull Executor executor, @NotNull ExecutionEnviro
       if (device == null) return null;
 
       final GeneralCommandLine command = getCommand(env, device);
-
-      final FlutterApp app = FlutterApp.start(env, project, module, mode, device, command,
-                                              StringUtil.capitalize(mode.mode()) + "App",
-                                              "StopApp");
-
-      // Stop the app if the Flutter SDK changes.
-      final FlutterSdkManager.Listener sdkListener = new FlutterSdkManager.Listener() {
-        @Override
-        public void flutterSdkRemoved() {
-          app.shutdownAsync();
-        }
-      };
-      FlutterSdkManager.getInstance(project).addListener(sdkListener);
-      Disposer.register(app, () -> FlutterSdkManager.getInstance(project).removeListener(sdkListener));
-
-      return app;
+      return getFlutterApp(env, device, project, module, mode, command);
     };
 
     final LaunchState launcher = new AttachState(env, mainFile.getAppDir(), mainFile.getFile(), this, createAppCallback);

flutter-idea/src/io/flutter/run/SdkRunConfig.java

@@ -187,28 +187,37 @@ public LaunchState getState(@NotNull Executor executor, @NotNull ExecutionEnviro
         }
       }
 
-      final FlutterApp app = FlutterApp.start(env, project, module, mode, device, command,
-                                              StringUtil.capitalize(mode.mode()) + "App",
-                                              "StopApp");
-
-      // Stop the app if the Flutter SDK changes.
-      final FlutterSdkManager.Listener sdkListener = new FlutterSdkManager.Listener() {
-        @Override
-        public void flutterSdkRemoved() {
-          app.shutdownAsync();
-        }
-      };
-      FlutterSdkManager.getInstance(project).addListener(sdkListener);
-      Disposer.register(app, () -> FlutterSdkManager.getInstance(project).removeListener(sdkListener));
-
-      return app;
+      return getFlutterApp(env, device, project, module, mode, command);
     };
 
     final LaunchState launcher = new LaunchState(env, mainFile.getAppDir(), mainFile.getFile(), this, createAppCallback);
     addConsoleFilters(launcher, env, mainFile, module);
     return launcher;
   }
 
+  static @NotNull FlutterApp getFlutterApp(@NotNull ExecutionEnvironment env,
+                                            @NotNull FlutterDevice device,
+                                            Project project,
+                                            Module module,
+                                            RunMode mode,
+                                            GeneralCommandLine command) throws ExecutionException {
+    final FlutterApp app = FlutterApp.start(env, project, module, mode, device, command,
+                                            StringUtil.capitalize(mode.mode()) + "App",
+                                            "StopApp");
+
+    // Stop the app if the Flutter SDK changes.
+    final FlutterSdkManager.Listener sdkListener = new FlutterSdkManager.Listener() {
+      @Override
+      public void flutterSdkRemoved() {
+        app.shutdownAsync();
+      }
+    };
+    FlutterSdkManager.getInstance(project).addListener(sdkListener);
+    Disposer.register(app, () -> FlutterSdkManager.getInstance(project).removeListener(sdkListener));
+
+    return app;
+  }
+
   protected void addConsoleFilters(@NotNull LaunchState launcher,
                                    @NotNull ExecutionEnvironment env,
                                    @NotNull MainFile mainFile,