Add the pdf plugin's source in src\pdf.

pdf/pdf.gyp

+{
+  'variables': {
+    'chromium_code': 1,
+    'pdf_engine%': 0,  # 0 PDFium
+  },
+  'target_defaults': {
+    'cflags': [
+      '-fPIC',
+    ],
+  },
+  'targets': [
+    {
+      'target_name': 'pdf',
+      'type': 'loadable_module',
+      'msvs_guid': '647863C0-C7A3-469A-B1ED-AD7283C34BED',
+      'dependencies': [
+        '../base/base.gyp:base',
+        '../net/net.gyp:net',
+        '../ppapi/ppapi.gyp:ppapi_cpp',
+        '../third_party/pdfium/pdfium.gyp:fpdfsdk',
+      ],
+      'xcode_settings': {
+        'INFOPLIST_FILE': 'Info.plist',
+      },
+      'mac_framework_dirs': [
+        '$(SDKROOT)/System/Library/Frameworks/ApplicationServices.framework/Frameworks',
+      ],
+      'ldflags': [ '-L<(PRODUCT_DIR)',],
+      'sources': [
+        'button.h',
+        'button.cc',
+        'chunk_stream.h',
+        'chunk_stream.cc',
+        'control.h',
+        'control.cc',
+        'document_loader.h',
+        'document_loader.cc',
+        'draw_utils.cc',
+        'draw_utils.h',
+        'fading_control.cc',
+        'fading_control.h',
+        'fading_controls.cc',
+        'fading_controls.h',
+        'instance.cc',
+        'instance.h',
+        'number_image_generator.cc',
+        'number_image_generator.h',
+        'out_of_process_instance.cc',
+        'out_of_process_instance.h',
+        'page_indicator.cc',
+        'page_indicator.h',
+        'paint_aggregator.cc',
+        'paint_aggregator.h',
+        'paint_manager.cc',
+        'paint_manager.h',
+        'pdf.cc',
+        'pdf.h',
+        'pdf.rc',
+        'progress_control.cc',
+        'progress_control.h',
+        'pdf_engine.h',
+        'preview_mode_client.cc',
+        'preview_mode_client.h',
+        'resource.h',
+        'resource_consts.h',
+        'thumbnail_control.cc',
+        'thumbnail_control.h',
+        '../chrome/browser/chrome_page_zoom_constants.cc',
+        '../content/common/page_zoom.cc',
+      ],
+      'conditions': [
+        ['pdf_engine==0', {
+          'sources': [
+            'pdfium/pdfium_assert_matching_enums.cc',
+            'pdfium/pdfium_engine.cc',
+            'pdfium/pdfium_engine.h',
+            'pdfium/pdfium_mem_buffer_file_read.cc',
+            'pdfium/pdfium_mem_buffer_file_read.h',
+            'pdfium/pdfium_mem_buffer_file_write.cc',
+            'pdfium/pdfium_mem_buffer_file_write.h',
+            'pdfium/pdfium_page.cc',
+            'pdfium/pdfium_page.h',
+            'pdfium/pdfium_range.cc',
+            'pdfium/pdfium_range.h',
+          ],
+        }],
+        ['OS!="win"', {
+          'sources!': [
+            'pdf.rc',
+          ],
+        }],
+        ['OS=="mac"', {
+          'mac_bundle': 1,
+          'product_name': 'PDF',
+          'product_extension': 'plugin',
+          # Strip the shipping binary of symbols so "Foxit" doesn't appear in
+          # the binary.  Symbols are stored in a separate .dSYM.
+          'variables': {
+            'mac_real_dsym': 1,
+          },
+          'sources+': [
+            'Info.plist'
+          ],
+        }],
+        ['OS=="win"', {
+          'defines': [
+            'COMPILE_CONTENT_STATICALLY',
+          ],
+          # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
+          'msvs_disabled_warnings': [ 4267, ],
+        }],
+        ['OS=="linux"', {
+          'configurations': {
+            'Release_Base': {
+              #'cflags': [ '-fno-weak',],  # get rid of symbols that strip doesn't remove.
+              # Don't do this for now since official builder will take care of it.  That
+              # way symbols can still be uploaded to the crash server.
+              #'ldflags': [ '-s',],  # strip local symbols from binary.
+            },
+          },
+          # Use a custom version script to prevent leaking the vendor name in
+          # visible symbols.
+          'ldflags': [
+            '-Wl,--version-script=<!(cd <(DEPTH) && pwd -P)/pdf/libpdf.map'
+          ],
+        }],
+      ],
+    },
+    {
+      'target_name': 'pdfium_test',
+      'type': 'executable',
+      'dependencies': [
+        '../base/base.gyp:base',
+        '../base/base.gyp:base_i18n',
+        '../third_party/pdfium/pdfium.gyp:fpdfsdk',
+      ],
+      'sources': [
+        'pdfium/pdfium_test.cc',
+      ],
+    }
+  ],
+  'conditions': [
+    # CrOS has a separate step to do this.
+    ['OS=="linux" and chromeos==0',
+      { 'targets': [
+        {
+          'target_name': 'pdf_linux_symbols',
+          'type': 'none',
+          'conditions': [
+            ['linux_dump_symbols==1', {
+              'actions': [
+                {
+                  'action_name': 'dump_symbols',
+                  'inputs': [
+                    '<(DEPTH)/build/linux/dump_app_syms',
+                    '<(PRODUCT_DIR)/dump_syms',
+                    '<(PRODUCT_DIR)/libpdf.so',
+                  ],
+                  'outputs': [
+                    '<(PRODUCT_DIR)/libpdf.so.breakpad.<(target_arch)',
+                  ],
+                  'action': ['<(DEPTH)/build/linux/dump_app_syms',
+                             '<(PRODUCT_DIR)/dump_syms',
+                             '<(linux_strip_binary)',
+                             '<(PRODUCT_DIR)/libpdf.so',
+                             '<@(_outputs)'],
+                  'message': 'Dumping breakpad symbols to <(_outputs)',
+                  'process_outputs_as_sources': 1,
+                },
+              ],
+              'dependencies': [
+                'pdf',
+                '../breakpad/breakpad.gyp:dump_syms',
+              ],
+            }],
+          ],
+        },
+      ],
+    },],  # OS=="linux" and chromeos==0
+  ],
+}