Bug 729784 - Fix documentation for fuzzy() and fuzzy-if(), and give image difference error messages in the same order as the parameters to them. r=dbaron

layout/tools/reftest/README.txt

@@ -106,13 +106,16 @@ must be one of the following:
                          fast on a 32-bit system but inordinately slow on a
                          64-bit system).
 
-      fuzzy  This allows a test to pass if the pixel value differences
-             are <= 2. It can also be used with '!=' to ensure that the
-             difference is greater than 2.
+      fuzzy(maxDiff, diffCount)
+          This allows a test to pass if the pixel value differences are <=
+          maxDiff and the total number of different pixels is <= diffCount.
+          It can also be used with '!=' to ensure that the difference is
+          greater than maxDiff.
 
-      fuzzy-if(condition) If the condition is met, the test is treated as if
-                          'fuzzy' had been specified. This is useful if there
-                          are differences on particular platforms.
+      fuzzy-if(condition, maxDiff, diffCount)
+          If the condition is met, the test is treated as if 'fuzzy' had been
+          specified. This is useful if there are differences on particular
+          platforms.
 
       require-or(cond1&&cond2&&...,fallback)
           Require some particular setup be performed or environmental

layout/tools/reftest/reftest.js

@@ -1456,7 +1456,7 @@ function RecordResult(testRunTime, errorMsg, scriptResults)
                 if (!equal) {
                     gDumpLog("REFTEST   IMAGE 1 (TEST): " + gCanvas1.toDataURL() + "\n");
                     gDumpLog("REFTEST   IMAGE 2 (REFERENCE): " + gCanvas2.toDataURL() + "\n");
-                    gDumpLog("REFTEST number of differing pixels: " + differences + " max difference: " + maxDifference.value + "\n");
+                    gDumpLog("REFTEST max difference: " + maxDifference.value + " number of differing pixels: " + differences + "\n");
                 } else {
                     gDumpLog("REFTEST   IMAGE: " + gCanvas1.toDataURL() + "\n");
                 }