pin find-on-page scrolls to content edges

 Bug: 6066283

This change also contains code to prevent find-on-page from scrolling in
unnecessary circumstances, for example when a match is already being displayed.

Change-Id: I555c84f8851a82e854d12cb34b8805c9d3f22f5e

1 files changed, 15 insertions, 10 deletions

diff --git a/Source/WebKit/android/WebCoreSupport/PlatformBridge.cpp b/Source/WebKit/android/WebCoreSupport/PlatformBridge.cpp
index b684a1a..e536701 100644
--- a/Source/WebKit/android/WebCoreSupport/PlatformBridge.cpp
+++ b/Source/WebKit/android/WebCoreSupport/PlatformBridge.cpp
@@ -49,6 +49,8 @@
 #include <wtf/android/AndroidThreading.h>
 #include <wtf/MainThread.h>
 
+#include <algorithm>
+
 using namespace android;
 
 namespace WebCore {
@@ -169,18 +171,21 @@ void PlatformBridge::updateTextfield(FrameView* frameView, Node* nodePtr, bool c
 }
 
 void PlatformBridge::setScrollPosition(ScrollView* scrollView, int x, int y) {
+    FrameView* frameView = scrollView->frameView();
+    if (!frameView) return;
     // Check to make sure the view is the main FrameView.
     android::WebViewCore *webViewCore = android::WebViewCore::getWebViewCore(scrollView);
-    if (webViewCore->mainFrame()->view() == scrollView)
-        webViewCore->scrollTo(x, y);
-    else {
-        FrameView* frameView = scrollView->frameView();
-        if (frameView) {
-            RenderView* renderer = frameView->frame()->contentRenderer();
-            if (renderer) {
-                RenderLayer* layer = renderer->layer();
-                layer->scrollToOffset(x, y);
-            }
+    if (webViewCore->mainFrame()->view() == scrollView) {
+        const IntRect& visibleContentRect = frameView->visibleContentRect();
+        x = std::max(0, std::min(frameView->contentsWidth(), x));
+        y = std::max(0, std::min(frameView->contentsHeight(), y));
+        if ((x != visibleContentRect.x()) || (y != visibleContentRect.y()))
+            webViewCore->scrollTo(x, y);
+    } else {
+        RenderView* renderer = frameView->frame()->contentRenderer();
+        if (renderer) {
+            RenderLayer* layer = renderer->layer();
+            layer->scrollToOffset(x, y);
         }
     }
 }