Add support for returning traces as streams in DevTools protocol

Related chromium-side change: https://codereview.chromium.org/1307073002

BUG=456845

Review URL: https://codereview.chromium.org/1307863003

git-svn-id: svn://svn.chromium.org/blink/trunk@201322 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/Source/core/inspector/CodeGeneratorInspector.py

@@ -114,7 +114,7 @@ class Capitalizer:
         str = possible_abbreviation.lower() + str[pos:]
         return str
 
-    ABBREVIATION = frozenset(["XHR", "DOM", "CSS"])
+    ABBREVIATION = frozenset(["XHR", "DOM", "CSS", "IO"])
 
 VALIDATOR_IFDEF_NAME = "ENABLE(ASSERT)"
 

third_party/WebKit/Source/core/inspector/InspectorTracingAgent.cpp

@@ -47,7 +47,7 @@ void InspectorTracingAgent::restore()
     emitMetadataEvents();
 }
 
-void InspectorTracingAgent::start(ErrorString*, const String* categoryFilter, const String*, const double*, PassRefPtrWillBeRawPtr<StartCallback> callback)
+void InspectorTracingAgent::start(ErrorString*, const String* categoryFilter, const String*, const double*, const String*, PassRefPtrWillBeRawPtr<StartCallback> callback)
 {
     ASSERT(m_state->getString(TracingAgentState::sessionId).isEmpty());
     m_state->setString(TracingAgentState::sessionId, IdentifiersFactory::createIdentifier());

third_party/WebKit/Source/core/inspector/InspectorTracingAgent.h

@@ -43,8 +43,8 @@ public:
     void disable(ErrorString*) override;
 
     // Protocol method implementations.
-    void start(ErrorString*, const String* categoryFilter, const String*, const double*, PassRefPtrWillBeRawPtr<StartCallback>) override;
-    virtual void end(ErrorString*, PassRefPtrWillBeRawPtr<EndCallback>);
+    void start(ErrorString*, const String* categoryFilter, const String*, const double*, const String*, PassRefPtrWillBeRawPtr<StartCallback>) override;
+    void end(ErrorString*, PassRefPtrWillBeRawPtr<EndCallback>) override;
 
     // Methods for other agents to use.
     void setLayerTreeId(int);

third_party/WebKit/Source/devtools/front_end/sdk/TracingManager.js

@@ -58,6 +58,11 @@ WebInspector.TracingManager = function(target)
  */
 WebInspector.TracingManager.EventPayload;
 
+WebInspector.TracingManager.TransferMode = {
+    ReportEvents: "ReportEvents",
+    ReturnAsStream: "ReturnAsStream"
+};
+
 WebInspector.TracingManager.prototype = {
     /**
      * @return {?WebInspector.Target}
@@ -112,7 +117,7 @@ WebInspector.TracingManager.prototype = {
             throw new Error("Tracing is already started");
         var bufferUsageReportingIntervalMs = 500;
         this._activeClient = client;
-        this._target.tracingAgent().start(categoryFilter, options, bufferUsageReportingIntervalMs, callback);
+        this._target.tracingAgent().start(categoryFilter, options, bufferUsageReportingIntervalMs, WebInspector.TracingManager.TransferMode.ReportEvents, callback);
         this._activeClient.tracingStarted();
     },
 

third_party/WebKit/Source/devtools/protocol.json

@@ -3254,6 +3254,42 @@
             }
         ]
     },
+    {
+        "domain": "IO",
+        "description": "Input/Output operations for streams produced by DevTools.",
+        "hidden": true,
+        "types": [
+            {
+                "id": "StreamHandle",
+                "type": "string"
+            }
+        ],
+        "commands": [
+            {
+                "name": "read",
+                "description": "Read a chunk of the stream",
+                "async": true,
+                "parameters": [
+                    { "name": "handle", "$ref": "StreamHandle", "description": "Handle of the stream to read." },
+                    { "name": "offset", "type": "integer", "optional": true, "description": "Seek to the specified offset before reading (if not specificed, proceed with offset following the last read)." },
+                    { "name": "size", "type": "integer", "optional": true,  "description": "Maximum number of bytes to read (left upon the agent discretion if not specified)." }
+                ],
+                "returns": [
+                    { "name": "data", "type": "string", "description": "Data that were read." },
+                    { "name": "eof", "type": "boolean", "description": "Set if the end-of-file condition occured while reading." }
+                ],
+                "handlers": ["browser"]
+            },
+            {
+                "name": "close",
+                "description": "Close the stream, discard any temporary backing storage.",
+                "parameters": [
+                    { "name": "handle", "$ref": "StreamHandle", "description": "Handle of the stream to close." }
+                ],
+                "handlers": ["browser"]
+            }
+        ]
+    },
     {
         "domain": "Timeline",
         "description": "Timeline domain is deprecated. Please use Tracing instead.",
@@ -4826,7 +4862,8 @@
                 "parameters": [
                     { "name": "categories", "type": "string", "optional": true, "description": "Category/tag filter" },
                     { "name": "options", "type": "string", "optional": true, "description": "Tracing options" },
-                    { "name": "bufferUsageReportingInterval", "type": "number", "optional": true, "description": "If set, the agent will issue bufferUsage events at this interval, specified in milliseconds" }
+                    { "name": "bufferUsageReportingInterval", "type": "number", "optional": true, "description": "If set, the agent will issue bufferUsage events at this interval, specified in milliseconds" },
+                    { "name": "transferMode", "type": "string", "enum": ["ReportEvents", "ReturnAsStream"], "optional": true, "description": "Whether to report trace events as series of dataCollected events or to save trace to a stream (defaults to <code>ReportEvents</code>)." }
                 ],
                 "handlers": ["browser", "renderer"]
             },
@@ -4868,6 +4905,9 @@
             {
                 "name": "tracingComplete",
                 "description": "Signals that tracing is stopped and there is no trace buffers pending flush, all data were delivered via dataCollected events.",
+                "parameters": [
+                    { "name": "stream", "$ref": "IO.StreamHandle", "optional": true, "description": "A handle of the stream that holds resulting trace data." }
+                ],
                 "handlers": ["browser"]
             },
             {