Depend on javascriptcore, generate webkit2 VAPI that uses it.

This gives us a means of using JS objects returned by UserContentManager
script messages directly from Vala.

* bindings/metadata/WebKit2-4.0.metadata: Tweak standard webkit2 VAPI to
  re-include methods that return javascriptcore objects.

* bindings/vapi/javascriptcore-4.0.vapi: Copy generated VAPI file into
  the tree, customise it so that it actually works.

* src/CMakeLists.txt: Generate the custom webkit2 VAPI, depend on
  javascriptcore and include in-tree javascriptcore VAPI in the client
  build.

* bindings/metadata/JSCore-3.0.metadata: Remove obsolete file.

bindings/metadata/JSCore-3.0.metadata

@@ -1,3 +0,0 @@
-GlobalContextRef skip
-ObjectRef skip
-

bindings/metadata/WebKit2-4.0.metadata

@@ -0,0 +1,14 @@
+
+JavascriptResult
+    .get_global_context nullable=false unowned=true
+    .get_value nullable=false unowned=true
+
+//Forward upstream
+Download
+  .failed#signal.error type="WebKit.DownloadError"
+PrintOperation
+  .failed#signal.error type="WebKit.PrintError"
+WebResource
+  .failed#signal.error type="GLib.Error"
+WebView
+  .load_failed#signal.error type="GLib.Error"

bindings/vapi/javascriptcore-4.0.vapi

@@ -0,0 +1,15 @@
+/* javascriptcore-4.0.vapi. */
+
+[CCode (cprefix = "JS", gir_namespace = "JavaScriptCore", gir_version = "4.0", lower_case_cprefix = "JS_", cheader_filename = "JavaScriptCore/JavaScript.h")]
+namespace JS {
+
+	[CCode (cname = "JSGlobalContextRef")]
+    [SimpleType]
+	public struct GlobalContext {
+	}
+
+	[CCode (cname = "JSValueRef")]
+    [SimpleType]
+	public struct Value {
+	}
+}

src/CMakeLists.txt

@@ -505,6 +505,7 @@ pkg_check_modules(DEPS REQUIRED
     gobject-introspection-1.0
     webkit2gtk-4.0>=${TARGET_WEBKIT}
     webkit2gtk-web-extension-4.0>=${TARGET_WEBKIT}
+    javascriptcoregtk-4.0>=${TARGET_WEBKIT}
     enchant>=1.6
     ${EXTRA_CLIENT_PKG_CONFIG}
 )
@@ -534,6 +535,7 @@ set(CLIENT_PACKAGES
   geary-engine
   gio-2.0
   gtk+-3.0
+  javascriptcore-4.0
   libcanberra
   libnotify
   libsecret-1
@@ -602,8 +604,8 @@ link_directories(${LIB_PATHS})
 add_definitions(${CFLAGS})
 
 set(VALAC_OPTIONS
-    --vapidir=${CMAKE_SOURCE_DIR}/bindings/vapi
     --vapidir=${CMAKE_BINARY_DIR}/src
+    --vapidir=${CMAKE_SOURCE_DIR}/bindings/vapi
     --metadatadir=${CMAKE_SOURCE_DIR}/bindings/metadata
     --target-glib=${TARGET_GLIB}
     --thread
@@ -636,6 +638,23 @@ set_property(
 )
 target_link_libraries(geary-engine m ${DEPS_LIBRARIES} sqlite3-unicodesn)
 
+# WebKit2GTK VAPI generation
+#################################################
+add_custom_target(webkit2gtk-vapi
+  DEPENDS "${CMAKE_BINARY_DIR}/src/webkit2gtk-4.0.vapi"
+)
+add_custom_command(
+    OUTPUT
+        ${CMAKE_BINARY_DIR}/src/webkit2gtk-4.0.vapi
+    DEPENDS
+        "${CMAKE_SOURCE_DIR}/bindings/metadata/WebKit2-4.0.metadata"
+        "${CMAKE_SOURCE_DIR}/bindings/vapi/javascriptcore-4.0.vapi"
+    WORKING_DIRECTORY
+        "${CMAKE_SOURCE_DIR}/bindings/metadata"
+    COMMAND
+        vapigen --library=webkit2gtk-4.0 --pkg gtk+-3.0 --pkg libsoup-2.4 --pkg javascriptcore-4.0 --vapidir=${CMAKE_SOURCE_DIR}/bindings/vapi --metadatadir=${CMAKE_SOURCE_DIR}/bindings/metadata --directory=${CMAKE_BINARY_DIR}/src `${PKG_CONFIG_EXECUTABLE} --variable=girdir gobject-introspection-1.0`/WebKit2-4.0.gir
+)
+
 # Client library (static lib used for building client and unit tests)
 #################################################
 
@@ -652,7 +671,7 @@ OPTIONS
 )
 
 add_library(geary-client STATIC ${CLIENT_VALA_C})
-add_dependencies(geary-client resource_copy webkitgtk-vapi)
+add_dependencies(geary-client resource_copy webkit2gtk-vapi)
 target_link_libraries(geary-client m ${DEPS_LIBRARIES} geary-engine)
 
 # Main client application binary

test/CMakeLists.txt

@@ -27,6 +27,7 @@ pkg_check_modules(DEPS REQUIRED
   gmime-2.6
   gthread-2.0
   gtk+-3.0
+  javascriptcoregtk-4.0
   libsoup-2.4
   webkit2gtk-4.0
 )
@@ -39,6 +40,7 @@ set(TEST_PACKAGES
   glib-2.0
   gmime-2.6
   gtk+-3.0
+  javascriptcore-4.0
   libsoup-2.4
   webkit2gtk-4.0
 )