Show small author portraits in Diffusion blame view

Summary: Depends on D18746. See PHI174. Adds small author portraits next to each blame line (this is similar to GitHub).

Test Plan:
My local test data isn't that great since I don't have commits from a lot of accounts, but looks functional:

{F5251056}

Reviewers: amckinley

Reviewed By: amckinley

Differential Revision: https://secure.phabricator.com/D18747

resources/celerity/map.php

@@ -73,7 +73,7 @@ return array(
     'rsrc/css/application/diffusion/diffusion-icons.css' => '0c15255e',
     'rsrc/css/application/diffusion/diffusion-readme.css' => '419dd5b6',
     'rsrc/css/application/diffusion/diffusion-repository.css' => 'ee6f20ec',
-    'rsrc/css/application/diffusion/diffusion-source.css' => '3a1056d8',
+    'rsrc/css/application/diffusion/diffusion-source.css' => 'd96b3f9f',
     'rsrc/css/application/diffusion/diffusion.css' => '45727264',
     'rsrc/css/application/feed/feed.css' => 'ecd4ec57',
     'rsrc/css/application/files/global-drag-and-drop.css' => 'b556a948',
@@ -572,7 +572,7 @@ return array(
     'diffusion-icons-css' => '0c15255e',
     'diffusion-readme-css' => '419dd5b6',
     'diffusion-repository-css' => 'ee6f20ec',
-    'diffusion-source-css' => '3a1056d8',
+    'diffusion-source-css' => 'd96b3f9f',
     'diviner-shared-css' => '896f1d43',
     'font-fontawesome' => 'e838e088',
     'font-lato' => 'c7ccd872',

src/applications/diffusion/controller/DiffusionBrowseController.php

@@ -969,6 +969,24 @@ final class DiffusionBrowseController extends DiffusionController {
 
     $handles = $viewer->loadHandles($phids);
 
+    $author_phids = array();
+    $author_map = array();
+    foreach ($blame_commits as $commit) {
+      $commit_identifier = $commit->getCommitIdentifier();
+
+      $author_phid = '';
+      if (isset($revision_map[$commit_identifier])) {
+        $revision_id = $revision_map[$commit_identifier];
+        $revision = $revisions[$revision_id];
+        $author_phid = $revision->getAuthorPHID();
+      } else {
+        $author_phid = $commit->getAuthorPHID();
+      }
+
+      $author_map[$commit_identifier] = $author_phid;
+      $author_phids[$author_phid] = $author_phid;
+    }
+
     $colors = array();
     if ($blame_commits) {
       $epochs = array();
@@ -1113,6 +1131,7 @@ final class DiffusionBrowseController extends DiffusionController {
     // blame outputs.
     $commit_links = $this->renderCommitLinks($blame_commits, $handles);
     $revision_links = $this->renderRevisionLinks($revisions, $handles);
+    $author_links = $this->renderAuthorLinks($author_map, $handles);
 
     if ($this->coverage) {
       require_celerity_resource('differential-changeset-view-css');
@@ -1145,6 +1164,7 @@ final class DiffusionBrowseController extends DiffusionController {
 
       $revision_link = null;
       $commit_link = null;
+      $author_link = null;
       $before_link = null;
 
       $style = 'background: '.$line['color'].';';
@@ -1152,6 +1172,7 @@ final class DiffusionBrowseController extends DiffusionController {
       if ($identifier && !$line['duplicate']) {
         if (isset($commit_links[$identifier])) {
           $commit_link = $commit_links[$identifier];
+          $author_link = $author_links[$author_map[$identifier]];
         }
 
         if (isset($revision_map[$identifier])) {
@@ -1185,6 +1206,7 @@ final class DiffusionBrowseController extends DiffusionController {
           $before_link);
 
         $object_links = array();
+        $object_links[] = $author_link;
         $object_links[] = $commit_link;
         if ($revision_link) {
           $object_links[] = phutil_tag('span', array(), '/');
@@ -1772,6 +1794,33 @@ final class DiffusionBrowseController extends DiffusionController {
     return array($identifiers, $commits);
   }
 
+  private function renderAuthorLinks(array $authors, $handles) {
+    $links = array();
+
+    foreach ($authors as $phid) {
+      if (!strlen($phid)) {
+        // This means we couldn't identify an author for the commit or the
+        // revision. We just render a blank for alignment.
+        $style = null;
+        $href = null;
+      } else {
+        $src = $handles[$phid]->getImageURI();
+        $style = 'background-image: url('.$src.');';
+        $href = $handles[$phid]->getURI();
+      }
+
+      $links[$phid] = javelin_tag(
+        $href ? 'a' : 'span',
+        array(
+          'class' => 'diffusion-author-link',
+          'style' => $style,
+          'href' => $href,
+        ));
+    }
+
+    return $links;
+  }
+
   private function renderCommitLinks(array $commits, $handles) {
     $links = array();
     foreach ($commits as $identifier => $commit) {

webroot/rsrc/css/application/diffusion/diffusion-source.css

@@ -66,7 +66,7 @@
 
 .diffusion-rev-link a,
 .diffusion-rev-link span {
-  margin: 2px 8px 0;
+  margin: 0 8px 0 0;
   display: inline-block;
 }
 
@@ -90,3 +90,13 @@
   -ms-user-select: none;
   user-select: none;
 }
+
+.diffusion-rev-link .diffusion-author-link {
+  display: inline-block;
+  padding: 0;
+  margin: 2px 4px -4px 4px;
+  width: 16px;
+  height: 16px;
+  background-size: 100% 100%;
+  background-repeat: no-repeat;
+}