Remove unused function fixZoom_ from find_in_page.js.

Clean up the find_in_page.js by removing unused function. This is a
preparation work for bug fixing.

Bug: 228585
Change-Id: Id20053f8623b8a25dba69c2779623854c2b4d666
Reviewed-on: https://chromium-review.googlesource.com/c/1341536Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Yi Su <mrsuyi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609272}

ios/chrome/browser/find_in_page/resources/find_in_page.js

@@ -651,20 +651,6 @@ __gCrWeb.findInPage.init = function(width, height) {
   __gCrWeb.findInPage.hasInitialized = true;
 };
 
-/**
- * When the GSA app detects a zoom change, we need to update our css.
- * @param {number} width Width of page.
- * @param {number} height Height of page.
- */
-function fixZoom_(width, height) {
-  pageWidth_ = width;
-  pageHeight_ = height;
-  if (styleElement_) {
-    removeStyle_();
-    addStyle_();
-  }
-};
-
 /**
  * Enable the __gCrWeb.findInPage module.
  * Mainly just adds the style for the classes.