Update DEPS for chromium roll, fix few sky issues

This updates DEPS to match the recent chromium roll and applies the
following changes to sky to accomodate the skia roll:

https://src.chromium.org/viewvc/blink?revision=184191&view=revision
https://src.chromium.org/viewvc/blink?revision=184289&view=revision

as well as adding #include <string> to WTFString.h so it compiles for
translation units that include this without #including <string>
themselves, which currently happens in a number of files in the android
build.

TBR=abarth@chromium.org

Review URL: https://codereview.chromium.org/682573003

engine/platform/graphics/Canvas2DLayerBridge.cpp

@@ -317,8 +317,6 @@ void Canvas2DLayerBridge::freeReleasedMailbox()
     }
     // Invalidate texture state in case the compositor altered it since the copy-on-write.
     if (mailboxInfo->m_image) {
-        if (isHidden() || releasedMailboxHasExpired())
-            mailboxInfo->m_image->getTexture()->resetFlag(static_cast<GrTextureFlags>(GrTexture::kReturnToCache_FlagBit));
         mailboxInfo->m_image->getTexture()->textureParamsModified();
         mailboxInfo->m_image.clear();
     }
@@ -505,9 +503,9 @@ void Canvas2DLayerBridge::mailboxReleased(const WebExternalTextureMailbox& mailb
                 // texture and remove the mailbox from list to avoid reusing it
                 // in future.
                 if (mailboxInfo->m_image) {
-                    mailboxInfo->m_image->getTexture()->resetFlag(
-                        static_cast<GrTextureFlags>(GrTexture::kReturnToCache_FlagBit));
-                    mailboxInfo->m_image->getTexture()->textureParamsModified();
+                    GrTexture* texture = mailboxInfo->m_image->getTexture();
+                    if (texture)
+                        texture->textureParamsModified();
                     mailboxInfo->m_image.clear();
                 }
                 size_t i = mailboxInfo - m_mailboxes.begin();

engine/wtf/text/WTFString.h

@@ -24,6 +24,7 @@
 
 // This file would be called String.h, but that conflicts with <string.h>
 // on systems without case-sensitive file systems.
+#include <string>
 
 #include "wtf/HashTableDeletedValueType.h"
 #include "wtf/WTFExport.h"