Introduce Image loader extension.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 605cd55113bf4211b0c1c766aed18f40921e8781..0da8e9caeff72646677253d5cce5d77ab0f31d7f 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -195,6 +195,9 @@
       # Disable file manager component extension by default.
       'file_manager_extension%': 0,
 
+      # Disable image loader component extension by default.
+      'image_loader_extension%': 0,
+
       # Python version.
       'python_ver%': '2.6',
 
@@ -469,11 +472,13 @@
           'use_titlecase_in_grd_files%': 1,
         }],
 
-        # Enable file manager extension on Chrome OS.
+        # Enable file manager and image loader extensions on Chrome OS.
         ['chromeos==1', {
           'file_manager_extension%': 1,
+          'image_loader_extension%': 1,
         }, {
           'file_manager_extension%': 0,
+          'image_loader_extension%': 0,
         }],
 
         ['OS=="win" or OS=="mac" or (OS=="linux" and chromeos==0)', {
@@ -679,6 +684,7 @@
     'enable_touch_ui%': '<(enable_touch_ui)',
     'use_xi2_mt%':'<(use_xi2_mt)',
     'file_manager_extension%': '<(file_manager_extension)',
+    'image_loader_extension%': '<(image_loader_extension)',
     'inside_chromium_build%': '<(inside_chromium_build)',
     'fastbuild%': '<(fastbuild)',
     'dcheck_always_on%': '<(dcheck_always_on)',
@@ -1380,6 +1386,9 @@
       ['file_manager_extension==1', {
         'grit_defines': ['-D', 'file_manager_extension'],
       }],
+      ['image_loader_extension==1', {
+        'grit_defines': ['-D', 'image_loader_extension'],
+      }],
       ['remoting==1', {
         'grit_defines': ['-D', 'remoting'],
       }],
@@ -1727,6 +1736,9 @@
       ['file_manager_extension==1', {
         'defines': ['FILE_MANAGER_EXTENSION=1'],
       }],
+      ['image_loader_extension==1', {
+        'defines': ['IMAGE_LOADER_EXTENSION=1'],
+      }],
       ['profiling==1', {
         'defines': ['ENABLE_PROFILING=1'],
       }],