Factor out text layer creation to its own method.

This sets the stage for allowing the use of multiple layers.

jquery.flot.js

@@ -171,7 +171,7 @@ Licensed under the MIT license.
 
 		var cache = this._textCache,
 			cacheHasText = false,
-			info, key;
+			key;
 
 		// Check whether the cache actually has any entries.
 
@@ -188,23 +188,13 @@ Licensed under the MIT license.
 
 		// Create the HTML text layer, if it doesn't already exist.
 
-		if (!this.text) {
-			this.text = $("<div></div>")
-				.addClass("flot-text")
-				.css({
-					position: "absolute",
-					top: 0,
-					left: 0,
-					bottom: 0,
-					right: 0
-				})
-				.insertAfter(this.element);
-		}
+		var layer = this.getTextLayer(),
+			info;
 
 		// Add all the elements to the text layer, then add it to the DOM at
 		// the end, so we only trigger a single redraw.
 
-		this.text.hide();
+		layer.hide();
 
 		for (key in cache) {
 			if (hasOwnProperty.call(cache, key)) {
@@ -213,7 +203,7 @@ Licensed under the MIT license.
 
 				if (info.active) {
 					if (!info.rendered) {
-						this.text.append(info.element);
+						layer.append(info.element);
 						info.rendered = true;
 					}
 				} else {
@@ -225,7 +215,31 @@ Licensed under the MIT license.
 			}
 		}
 
-		this.text.show();
+		layer.show();
+	};
+
+	// Creates (if necessary) and returns the text overlay container.
+	//
+	// @return {object} The jQuery-wrapped text-layer div.
+
+	Canvas.prototype.getTextLayer = function() {
+
+		// Create the text layer if it doesn't exist
+
+		if (!this.text) {
+			this.text = $("<div></div>")
+				.addClass("flot-text")
+				.css({
+					position: "absolute",
+					top: 0,
+					left: 0,
+					bottom: 0,
+					right: 0
+				})
+				.insertAfter(this.element);
+		}
+
+		return this.text;
 	};
 
 	// Creates (if necessary) and returns a text info object.