Third round of matrixconvolution rebaselines, and removal from ignored-tests.txt.

expectations/gm/Test-Mac10.6-MacMini4.1-GeForce320M-x86-Release/expected-results.json

 {
   "actual-results": {
     "failed": null, 
     "failure-ignored": null, 
     "no-comparison": null, 
     "succeeded": null
   }, 
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
@@ skipping 8822 matching lines @@
           "bitmap-64bitMD5", 
           17565121515344328262
         ]
       ], 
       "ignore-failure": false
     }, 
     "matrixconvolution_pdf-poppler.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          10325481294731675779
+          12422744673906560584
         ]
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }, 
     "megalooper_0x0_565.png": {
       "allowed-digests": [
         [
@@ skipping 4177 matching lines @@
           10424380103329133154
         ]
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }
   }
 }