Implement flex properties in java version as well

Summary: Implement flexShrink flexGrow and flexBasis in java as well because it will take a bit until the java code is removed

Reviewed By: lucasr

Differential Revision: D3753231

fbshipit-source-id: ea41d887cd99d1f03d2bc876a2fd7141dbe48320

java/com/facebook/csslayout/CSSNodeAPI.java

@@ -54,6 +54,12 @@ public interface CSSNodeAPI<CSSNodeType extends CSSNodeAPI> {
   void setWrap(CSSWrap flexWrap);
   float getFlex();
   void setFlex(float flex);
+  float getFlexGrow();
+  void setFlexGrow(float flexGrow);
+  float getFlexShrink();
+  void setFlexShrink(float flexShrink);
+  float getFlexBasis();
+  void setFlexBasis(float flexBasis);
   Spacing getMargin();
   void setMargin(int spacingType, float margin);
   Spacing getPadding();