Merge branch 'release-boba' into masterupstream/fabian-merge-v4.0.0

# Conflicts:
#	circle.yml
#	include/mbgl/style/expression/let.hpp
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/geometry/LatLngBounds.java
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapGestureDetector.java
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapKeyListener.java
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapView.java
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapboxMap.java
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/Projection.java
#	platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/Transform.java
#	platform/android/MapboxGLAndroidSDK/src/test/java/com/mapbox/mapboxsdk/geometry/LatLngBoundsTest.java
#	platform/android/MapboxGLAndroidSDKTestApp/src/main/AndroidManifest.xml
#	platform/android/gradle/dependencies.gradle
#	platform/android/src/example_custom_layer.cpp
#	platform/android/src/geojson/point.cpp
#	platform/darwin/src/NSPredicate+MGLAdditions.mm
#	platform/darwin/test/MGLExpressionTests.mm
#	platform/ios/Mapbox-iOS-SDK-nightly-dynamic.podspec
#	platform/ios/Mapbox-iOS-SDK-symbols.podspec
#	platform/ios/Mapbox-iOS-SDK.podspec
#	platform/ios/app/MBXViewController.m
#	src/mbgl/renderer/layers/render_custom_layer.cpp
#	src/mbgl/style/conversion/filter.cpp
#	src/mbgl/style/expression/interpolate.cpp
#	src/mbgl/style/expression/value.cpp
#	test/style/filter.test.cpp

1 files changed, 6 insertions, 9 deletions

diff --git a/include/mbgl/style/function/source_function.hpp b/include/mbgl/style/function/source_function.hpp
index d3caa90ee5..5b51d0bf81 100644
--- a/include/mbgl/style/function/source_function.hpp
+++ b/include/mbgl/style/function/source_function.hpp
@@ -30,15 +30,15 @@ public:
             IdentityStops<T>>>;
 
     SourceFunction(std::unique_ptr<expression::Expression> expression_)
-        : expression(std::move(expression_))
+        : isExpression(true),
+          expression(std::move(expression_))
     {
         assert(expression::isZoomConstant(*expression));
         assert(!expression::isFeatureConstant(*expression));
     }
     
-    SourceFunction(std::string property_, Stops stops_, optional<T> defaultValue_ = {})
-        : property(std::move(property_)),
-          stops(std::move(stops_)),
+    SourceFunction(const std::string& property, const Stops& stops, optional<T> defaultValue_ = {})
+        : isExpression(false),
           defaultValue(std::move(defaultValue_)),
           expression(stops.match([&] (const IdentityStops<T>&) {
               return expression::Convert::fromIdentityFunction(expression::valueTypeToExpressionType<T>(), property);
@@ -67,15 +67,12 @@ public:
     }
 
     bool useIntegerZoom = false;
+    bool isExpression;
 
     const expression::Expression& getExpression() const { return *expression; }
 
-    // retained for compatibility with pre-expression function API
-    std::string property;
-    Stops stops;
-    optional<T> defaultValue;
-
 private:
+    optional<T> defaultValue;
     std::shared_ptr<expression::Expression> expression;
 };