Change parseFloat() to Number()

Number() is a bit less forgiving than parseFloat() and is more likely to generate NaN rather than some random number.  An audit of each case shows nowhere that parseFloat()’s features are needed.

generators/php.js

@@ -285,7 +285,7 @@ Blockly.PHP.getAdjusted = function(block, atId, opt_delta, opt_negate,
 
   if (Blockly.isNumber(at)) {
     // If the index is a naked number, adjust it right now.
-    at = parseFloat(at) + delta;
+    at = Number(at) + delta;
     if (opt_negate) {
       at = -at;
     }