Adds DevTools commands for forced viewport override.

third_party/WebKit/Source/web/InspectorEmulationAgent.cpp

Index: third_party/WebKit/Source/web/InspectorEmulationAgent.cpp
diff --git a/third_party/WebKit/Source/web/InspectorEmulationAgent.cpp b/third_party/WebKit/Source/web/InspectorEmulationAgent.cpp
index 6f5c53ed71d7a2b8efe9a0e4b56311ca6fd258c8..38c9a3c3af8102c8c1c3fe0449a5b5733b633806 100644
--- a/third_party/WebKit/Source/web/InspectorEmulationAgent.cpp
+++ b/third_party/WebKit/Source/web/InspectorEmulationAgent.cpp
@@ -11,6 +11,7 @@
 #include "platform/geometry/DoubleRect.h"
 #include "platform/scheduler/CancellableTaskFactory.h"
 #include "public/platform/Platform.h"
+#include "public/platform/WebFloatPoint.h"
 #include "public/platform/WebThread.h"
 #include "public/platform/WebViewScheduler.h"
 #include "web/DevToolsEmulator.h"
@@ -23,6 +24,10 @@ namespace EmulationAgentState {
 static const char scriptExecutionDisabled[] = "scriptExecutionDisabled";
 static const char touchEventEmulationEnabled[] = "touchEventEmulationEnabled";
 static const char emulatedMedia[] = "emulatedMedia";
+static const char forcedViewportEnabled[] = "forcedViewportEnabled";
+static const char forcedViewportX[] = "forcedViewportX";
+static const char forcedViewportY[] = "forcedViewportY";
+static const char forcedViewportScale[] = "forcedViewportScale";
 }
 
 InspectorEmulationAgent* InspectorEmulationAgent::create(WebLocalFrameImpl* webLocalFrameImpl, Client* client)
@@ -54,6 +59,9 @@ void InspectorEmulationAgent::restore()
     String emulatedMedia;
     m_state->getString(EmulationAgentState::emulatedMedia, &emulatedMedia);
     setEmulatedMedia(&error, emulatedMedia);
+    if (m_state->booleanProperty(EmulationAgentState::forcedViewportEnabled, false)) {
+        forceViewport(&error, m_state->doubleProperty(EmulationAgentState::forcedViewportX, 0), m_state->doubleProperty(EmulationAgentState::forcedViewportY, 0), m_state->doubleProperty(EmulationAgentState::forcedViewportScale, 1));
+    }
 }
 
 void InspectorEmulationAgent::disable(ErrorString*)
@@ -62,6 +70,33 @@ void InspectorEmulationAgent::disable(ErrorString*)
     setScriptExecutionDisabled(&error, false);
     setTouchEmulationEnabled(&error, false, protocol::Maybe<String>());
     setEmulatedMedia(&error, String());
+    resetViewport(&error);
+}
+
+void InspectorEmulationAgent::forceViewport(ErrorString* error, double x, double y, double scale)
+{
+    if (x < 0 || y < 0) {
+        *error = "Coordinates must be non-negative";
+        return;
+    }
+
+    if (scale <= 0) {
+        *error = "Scale must be positive";
+        return;
+    }
+
+    m_state->setBoolean(EmulationAgentState::forcedViewportEnabled, true);
+    m_state->setDouble(EmulationAgentState::forcedViewportX, x);
+    m_state->setDouble(EmulationAgentState::forcedViewportY, y);
+    m_state->setDouble(EmulationAgentState::forcedViewportScale, scale);
+
+    webViewImpl()->devToolsEmulator()->forceViewport(WebFloatPoint(x, y), scale);
+}
+
+void InspectorEmulationAgent::resetViewport(ErrorString*)
+{
+    m_state->setBoolean(EmulationAgentState::forcedViewportEnabled, false);
+    webViewImpl()->devToolsEmulator()->resetViewport();
 }
 
 void InspectorEmulationAgent::resetPageScaleFactor(ErrorString*)