Introduce the app store compliance configure option

QtWebEngine requires this in order to disable code that is not allowed
on the Mac App Store. The option is too generic to go directly into
QtWebEngine however, as it can be used to toggle additional features in
qtbase as well as on platforms other than macOS.

Change-Id: I556298f4b654a8904c33002ef097a75e2e38938e
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@qt.io>
Reviewed-by: Jake Petroules <jake.petroules@qt.io>

config_help.txt

@@ -90,6 +90,11 @@ Build options:
   -device <name> ....... Cross-compile for device <name>
   -device-option <key=value> ... Add option for the device mkspec
 
+  -appstore-compliant .. Disable code that is not allowed in platform app stores.
+                         This is on by default for platforms which require distribution
+                         through an app store by default, in particular Android,
+                         iOS, tvOS, watchOS, and Universal Windows Platform. [auto]
+
   -qtnamespace <name> .. Wrap all Qt library code in 'namespace <name> {...}'.
   -qtlibinfix <infix> .. Rename all libQt5*.so to libQt5*<infix>.so.
 

configure.json

@@ -57,6 +57,7 @@
 
             "accessibility": "boolean",
             "android-style-assets": "boolean",
+            "appstore-compliant": "boolean",
             "avx": "boolean",
             "avx2": "boolean",
             "avx512": { "type": "boolean", "name": "avx512f" },
@@ -526,6 +527,12 @@
             "autoDetect": "features.debug",
             "output": [ "privateFeature", "publicQtConfig" ]
         },
+        "appstore-compliant": {
+            "label": "App store compliance",
+            "purpose": "Disables code that is not allowed in platform app stores",
+            "autoDetect": "config.uikit || config.android || config.winrt",
+            "output": [ "publicFeature" ]
+        },
         "simulator_and_device": {
             "label": "Build for both simulator and device",
             "condition": "config.uikit && input.sdk == ''",
@@ -1102,6 +1109,11 @@ Configure with '-qreal float' to create a build that is binary-compatible with 5
                 {
                     "message": "Build parts",
                     "type": "buildParts"
+                },
+                {
+                    "type": "feature",
+                    "args": "appstore-compliant",
+                    "condition": "config.darwin || config.android || config.winrt || config.win32"
                 }
             ]
         }, {