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, 23 insertions, 18 deletions

diff --git a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/PropertyValue.java b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/PropertyValue.java
index a57c440df4..fa1779a6c7 100644
--- a/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/PropertyValue.java
+++ b/platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/PropertyValue.java
@@ -4,8 +4,9 @@ import android.support.annotation.ColorInt;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 
+import com.google.gson.JsonArray;
 import com.mapbox.mapboxsdk.exceptions.ConversionException;
-import com.mapbox.mapboxsdk.style.functions.Function;
+import com.mapbox.mapboxsdk.style.expressions.Expression;
 import com.mapbox.mapboxsdk.utils.ColorUtils;
 
 import timber.log.Timber;
@@ -40,35 +41,39 @@ public class PropertyValue<T> {
   }
 
   /**
-   * Returns if this is a function.
+   * Returns if this is a expression.
    *
-   * @return true if is a function, false if not
+   * @return true if this is a expression, false if not
    */
-  public boolean isFunction() {
-    return !isNull() && value instanceof Function;
+  public boolean isExpression() {
+    return !isNull() && value instanceof JsonArray;
   }
 
   /**
-   * Returns if this is a value.
+   * Get the expression of the property.
    *
-   * @return true if is a value, false if not
+   * @return the property expression
    */
-  public boolean isValue() {
-    return !isNull() && !isFunction();
-  }
-
   @Nullable
-  public Function<?, T> getFunction() {
-    if (isFunction()) {
-      // noinspection unchecked
-      return (Function<?, T>) value;
+  public Expression getExpression() {
+    if (isExpression()) {
+      return Expression.Converter.convert((JsonArray) value);
     } else {
-      Timber.w("not a function, try value");
+      Timber.w("not a expression, try value");
       return null;
     }
   }
 
   /**
+   * Returns if this is a value.
+   *
+   * @return true if is a value, false if not
+   */
+  public boolean isValue() {
+    return !isNull() && !isExpression();
+  }
+
+  /**
    * Get the value of the property.
    *
    * @return the property value
@@ -77,7 +82,7 @@ public class PropertyValue<T> {
   public T getValue() {
     if (isValue()) {
       // noinspection unchecked
-      return (T) value;
+      return value;
     } else {
       Timber.w("not a value, try function");
       return null;
@@ -114,4 +119,4 @@ public class PropertyValue<T> {
   public String toString() {
     return String.format("%s: %s", name, value);
   }
-}
+}
\ No newline at end of file