[android] Fix calculation / clearing of cached glyph advance

#977

android/src/main/java/com/horcrux/svg/TSpanView.java

@@ -70,6 +70,11 @@ class TSpanView extends TextView {
         super.invalidate();
     }
 
+    void clearCache() {
+        mCachedPath = null;
+        super.clearCache();
+    }
+
     @Override
     void draw(Canvas canvas, Paint paint, float opacity) {
         if (mContent != null) {

android/src/main/java/com/horcrux/svg/TextView.java

@@ -51,7 +51,7 @@ class TextView extends GroupView {
             return;
         }
         super.invalidate();
-        clearChildCache();
+        getTextContainer().clearChildCache();
     }
 
     void clearCache() {
@@ -246,4 +246,13 @@ class TextView extends GroupView {
         return advance;
     }
 
+    TextView getTextContainer() {
+        TextView node = this;
+        ViewParent parent = this.getParent();
+        while (parent instanceof TextView) {
+            node = (TextView) parent;
+            parent = node.getParent();
+        }
+        return node;
+    }
 }