DevTools: optimize screencast for slower devices.

third_party/WebKit/Source/devtools/protocol.json

Index: third_party/WebKit/Source/devtools/protocol.json
diff --git a/third_party/WebKit/Source/devtools/protocol.json b/third_party/WebKit/Source/devtools/protocol.json
index 813bb5d13ca10c3c4fecf248b4efc231b68a43f9..c869d8de140d03459d72a9a814a1572161217c74 100644
--- a/third_party/WebKit/Source/devtools/protocol.json
+++ b/third_party/WebKit/Source/devtools/protocol.json
@@ -413,7 +413,8 @@
                     { "name": "format", "type": "string", "optional": true, "enum": ["jpeg", "png"], "description": "Image compression format." },
                     { "name": "quality", "type": "integer", "optional": true, "description": "Compression quality from range [0..100]." },
                     { "name": "maxWidth", "type": "integer", "optional": true, "description": "Maximum screenshot width." },
-                    { "name": "maxHeight", "type": "integer", "optional": true, "description": "Maximum screenshot height." }
+                    { "name": "maxHeight", "type": "integer", "optional": true, "description": "Maximum screenshot height." },
+                    { "name": "everyNthFrame", "type": "integer", "optional": true, "description": "Send every n-th frame." }
                 ],
                 "hidden": true,
                 "handlers": ["browser", "renderer"]
@@ -427,9 +428,6 @@
             {
                 "name": "screencastFrameAck",
                 "description": "Acknowledges that a screencast frame has been received by the frontend.",
-                "parameters": [
-                    { "name": "frameNumber", "type": "integer", "description": "Frame number." }
-                ],
                 "hidden": true,
                 "handlers": ["browser"]
             },
@@ -555,8 +553,7 @@
                 "description": "Compressed image data requested by the <code>startScreencast</code>.",
                 "parameters": [
                     { "name": "data", "type": "string", "description": "Base64-encoded compressed image." },
-                    { "name": "metadata", "$ref": "ScreencastFrameMetadata", "description": "Screencast frame metadata."},
-                    { "name": "frameNumber", "type": "integer", "optional": true, "description": "Frame number."}
+                    { "name": "metadata", "$ref": "ScreencastFrameMetadata", "description": "Screencast frame metadata."}
                 ],
                 "hidden": true,
                 "handlers": ["browser"]