Fix the dynamic browser action setIcon path to work with any size icon.

chrome/test/data/extensions/api_test/browser_action/no_icon/background.js

Index: chrome/test/data/extensions/api_test/browser_action/no_icon/background.js
diff --git a/chrome/test/data/extensions/api_test/browser_action/no_icon/background.js b/chrome/test/data/extensions/api_test/browser_action/no_icon/background.js
index 7d8c6c9e814d483bef7be99efb1341c809c10560..044efa2d14dc6ac78a8934acd4d926573aa220fa 100644
--- a/chrome/test/data/extensions/api_test/browser_action/no_icon/background.js
+++ b/chrome/test/data/extensions/api_test/browser_action/no_icon/background.js
@@ -3,18 +3,18 @@
 // found in the LICENSE file.
 
 var canvas = document.getElementById("canvas").getContext('2d').
-    getImageData(0, 0, 19, 19);
+    getImageData(0, 0, 21, 21);

[Devlin, 2016/01/13 19:58:12]

Were these chosen as sizes that are unused?

[Evan Stade, 2016/01/14 01:59:19]

yea, pretty much arbitrary. As the comment in the test states, I didn't want x /
16 or x / 19 to come out to a scale factor that's likely to appear on any device
that might run these tests, because then the tests are not as easy to write (as
representations will get automatically added for the active scale factor, so
testing their non-existence doesn't work).

 var canvasHD = document.getElementById("canvas").getContext('2d').
-    getImageData(0, 0, 38, 38);
+    getImageData(0, 0, 42, 42);
 
 var setIconParamQueue = [
   {imageData: canvas},
   {path: 'icon.png'},
-  {imageData: {'19': canvas, '38': canvasHD}},
-  {path: {'19': 'icon.png', '38': 'icon.png'}},
-  {imageData: {'19': canvas}},
-  {path: {'19': 'icon.png'}},
-  {imageData: {'38': canvasHD}},
+  {imageData: {'21': canvas, '42': canvasHD}},
+  {path: {'21': 'icon.png', '42': 'icon.png'}},
+  {imageData: {'21': canvas}},
+  {path: {'21': 'icon.png'}},
+  {imageData: {'42': canvasHD}},
   {imageData: {}},
   {path: {}},
 ];