Fix RichTextLength with close tags in succession

The RichTextSubStringMaker::Consume function was returning a wrong value when
the function was called by itself. It was returning `true` in the situation.
This commit fixes it by returning the recursive call's return value.

Author: majecty

Assets/RichTextHelper/RichTextHelper.cs

@@ -117,8 +117,7 @@ public bool Consume()
                 }
                 if (IsConsumable())
                 {
-                    Consume();
-                    return true;
+                    return Consume();
                 }
                 else
                 {

Assets/test/RichTextHelperTest.cs

@@ -32,6 +32,7 @@ public void SimpleTest() {
 
         var sampleText = "UnityTest behaves ";
         Assert.AreEqual(sampleText.RichTextSubString(sampleText.Length), sampleText);
+        Assert.AreEqual(sampleText.RichTextLength(), sampleText.Length);
     }
 
     [Test]
@@ -40,6 +41,7 @@ public void TagTest()
         var sampleTagText = "<color=#000>blah</color>x";
         Assert.AreEqual(sampleTagText.RichTextSubString(5), sampleTagText);
         Assert.AreEqual(sampleTagText.RichTextSubString(1), "<color=#000>b</color>");
+        Assert.AreEqual(sampleTagText.RichTextLength(), 5);
     }
 
     [Test]
@@ -51,6 +53,7 @@ public void NestedTest()
         Assert.AreEqual(sampleTagText.RichTextSubString(2), "<color=#000>a<i>b</i></color>");
         Assert.AreEqual(sampleTagText.RichTextSubString(3), "<color=#000>a<i>b<b>c</b></i></color>");
         Assert.AreEqual(sampleTagText.RichTextSubString(4), "<color=#000>a<i>b<b>c</b>d</i></color>");
+        Assert.AreEqual(sampleTagText.RichTextLength(), 5);
     }
 
     [Test]
@@ -62,5 +65,6 @@ public void CloseTagIsLast()
         Assert.AreEqual(sampleTagText.RichTextSubString(2), "<color=#000>a<i>b</i></color>");
         Assert.AreEqual(sampleTagText.RichTextSubString(3), "<color=#000>a<i>b<b>c</b></i></color>");
         Assert.AreEqual(sampleTagText.RichTextSubString(4), "<color=#000>a<i>b<b>c</b>d</i></color>");
+        Assert.AreEqual(sampleTagText.RichTextLength(), 4);
     }
 }