When parsing flavors, handle Xcode build configurations that are not lowercase (#161455)

The flavors/Xcode build config/Xcode scheme matching logic tries to be
permissive with casing. Instead of passing the lower-cased config into
`xcodebuild`, instead pass the real configuration name to get the right
casing.

Fixes https://github.com/flutter/flutter/issues/85643

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we expect every widget to implement].
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above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
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packages/flutter_tools/lib/src/ios/xcodeproj.dart

@@ -506,14 +506,14 @@ class XcodeProjectInfo {
 
   /// Checks whether the [buildConfigurations] contains the specified string, without
   /// regard to case.
-  bool hasBuildConfigurationForBuildMode(String buildMode) {
+  String? _existingBuildConfigurationForBuildMode(String buildMode) {
     buildMode = buildMode.toLowerCase();
     for (final String name in buildConfigurations) {
       if (name.toLowerCase() == buildMode) {
-        return true;
+        return name;
       }
     }
-    return false;
+    return null;
   }
 
   /// Returns unique scheme matching [buildInfo], or null, if there is no unique
@@ -547,8 +547,11 @@ class XcodeProjectInfo {
       return null;
     }
     final String expectedConfiguration = expectedBuildConfigurationFor(buildInfo, scheme);
-    if (hasBuildConfigurationForBuildMode(expectedConfiguration)) {
-      return expectedConfiguration;
+    final String? buildConfigurationForBuildMode = _existingBuildConfigurationForBuildMode(
+      expectedConfiguration,
+    );
+    if (buildConfigurationForBuildMode != null) {
+      return buildConfigurationForBuildMode;
     }
     final String baseConfiguration = _baseConfigurationFor(buildInfo);
     return _uniqueMatch(buildConfigurations, (String candidate) {

packages/flutter_tools/test/general.shard/ios/xcodeproj_test.dart

@@ -919,12 +919,15 @@ Information about project "Runner":
         <String>[
           'debug (free)',
           'Debug paid',
+          'debug (premium)',
           'profile - Free',
           'Profile-Paid',
+          'Profile-Premium',
           'release - Free',
           'Release-Paid',
+          'release-premium',
         ],
-        <String>['Free', 'Paid'],
+        <String>['Free', 'Paid', 'premium'],
         logger,
       );
 
@@ -952,6 +955,30 @@ Information about project "Runner":
         ),
         'Debug paid',
       );
+      expect(
+        info.buildConfigurationFor(
+          const BuildInfo(
+            BuildMode.debug,
+            'premium',
+            treeShakeIcons: false,
+            packageConfigPath: '.dart_tool/package_config.json',
+          ),
+          'premium',
+        ),
+        'debug (premium)',
+      );
+      expect(
+        info.buildConfigurationFor(
+          const BuildInfo(
+            BuildMode.debug,
+            'premium',
+            treeShakeIcons: false,
+            packageConfigPath: '.dart_tool/package_config.json',
+          ),
+          'Premium',
+        ),
+        'debug (premium)',
+      );
       expect(
         info.buildConfigurationFor(
           const BuildInfo(
@@ -964,6 +991,30 @@ Information about project "Runner":
         ),
         'profile - Free',
       );
+      expect(
+        info.buildConfigurationFor(
+          const BuildInfo(
+            BuildMode.profile,
+            'paid',
+            treeShakeIcons: false,
+            packageConfigPath: '.dart_tool/package_config.json',
+          ),
+          'paid',
+        ),
+        'Profile-Paid',
+      );
+      expect(
+        info.buildConfigurationFor(
+          const BuildInfo(
+            BuildMode.profile,
+            'premium',
+            treeShakeIcons: false,
+            packageConfigPath: '.dart_tool/package_config.json',
+          ),
+          'Premium',
+        ),
+        'Profile-Premium',
+      );
       expect(
         info.buildConfigurationFor(
           const BuildInfo(
@@ -976,6 +1027,18 @@ Information about project "Runner":
         ),
         'Release-Paid',
       );
+      expect(
+        info.buildConfigurationFor(
+          const BuildInfo(
+            BuildMode.release,
+            'PREMIUM',
+            treeShakeIcons: false,
+            packageConfigPath: '.dart_tool/package_config.json',
+          ),
+          'PREMIUM',
+        ),
+        'release-premium',
+      );
     },
   );