fix: crash on systemPreferences.getAccentColor() (#18144)

atom/browser/ui/cocoa/NSColor+Hex.h

@@ -10,6 +10,8 @@
 #import <Cocoa/Cocoa.h>
 
 @interface NSColor (Hex)
+- (NSString*)hexadecimalValue;
+- (NSString*)RGBAValue;
 + (NSColor*)colorWithHexColorString:(NSString*)hex;
 @end
 

atom/browser/ui/cocoa/NSColor+Hex.mm

@@ -8,17 +8,65 @@
 
 @implementation NSColor (Hex)
 
+- (NSString*)RGBAValue {
+  double redFloatValue, greenFloatValue, blueFloatValue, alphaFloatValue;
+
+  NSColor* convertedColor =
+      [self colorUsingColorSpaceName:NSCalibratedRGBColorSpace];
+
+  if (convertedColor) {
+    [convertedColor getRed:&redFloatValue
+                     green:&greenFloatValue
+                      blue:&blueFloatValue
+                     alpha:&alphaFloatValue];
+
+    int redIntValue = redFloatValue * 255.99999f;
+    int greenIntValue = greenFloatValue * 255.99999f;
+    int blueIntValue = blueFloatValue * 255.99999f;
+    int alphaIntValue = alphaFloatValue * 255.99999f;
+
+    return
+        [NSString stringWithFormat:@"%02x%02x%02x%02x", redIntValue,
+                                   greenIntValue, blueIntValue, alphaIntValue];
+  }
+
+  return nil;
+}
+
+- (NSString*)hexadecimalValue {
+  double redFloatValue, greenFloatValue, blueFloatValue;
+
+  NSColor* convertedColor =
+      [self colorUsingColorSpaceName:NSCalibratedRGBColorSpace];
+
+  if (convertedColor) {
+    [convertedColor getRed:&redFloatValue
+                     green:&greenFloatValue
+                      blue:&blueFloatValue
+                     alpha:NULL];
+
+    int redIntValue = redFloatValue * 255.99999f;
+    int greenIntValue = greenFloatValue * 255.99999f;
+    int blueIntValue = blueFloatValue * 255.99999f;
+
+    return [NSString stringWithFormat:@"#%02x%02x%02x", redIntValue,
+                                      greenIntValue, blueIntValue];
+  }
+
+  return nil;
+}
+
 + (NSColor*)colorWithHexColorString:(NSString*)inColorString {
   unsigned colorCode = 0;
-  unsigned char redByte, greenByte, blueByte;
 
   if (inColorString) {
     NSScanner* scanner = [NSScanner scannerWithString:inColorString];
     (void)[scanner scanHexInt:&colorCode];  // ignore error
   }
-  redByte = (unsigned char)(colorCode >> 16);
-  greenByte = (unsigned char)(colorCode >> 8);
-  blueByte = (unsigned char)(colorCode);  // masks off high bits
+
+  unsigned char redByte = (unsigned char)(colorCode >> 16);
+  unsigned char greenByte = (unsigned char)(colorCode >> 8);
+  unsigned char blueByte = (unsigned char)(colorCode);  // masks off high bits
 
   return [NSColor colorWithCalibratedRed:(CGFloat)redByte / 0xff
                                    green:(CGFloat)greenByte / 0xff