Bug 488855 - [Win32] Browser widget under windows calls a method in the wrong thread

The problem is that Internet Explorer sometimes calls 'WebSite#MapUrlToZone' from
non-main thread. This causes errors in 'Widget#checkWidget' when 'WebSite' tries to
get to its 'IE' parent via .getParent(). In order to solve the problem I removed the
code in question; now 'IE' tells 'WebSite' what to do.

I also noticed that there are other similar pieces of code, for example in
'WebSite#ProcessUrlAction'. However, it uses '_getUrl().startsWith(IE.ABOUT_BLANK)'
this time. I found that 'WebSite#MapUrlToZone' also used this approach previously,
but it was changed due to performance reasons. Still, it's not clear whether all
instances of '_getUrl().startsWith(IE.ABOUT_BLANK)' can be changed safely to
'IE#isAboutBlank' and I don't have the time to test it, so I left it as is.

I tried to test the original problem for which 'WebSite#MapUrlToZone' was made,
but it no longer reproduces for me. Probably it was solved independently in new IE.

Change-Id: Icd27bb6481e4f6792fc844380d0da9dbdc82adff
Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>

2 files changed, 21 insertions, 11 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/IE.java b/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/IE.java
index 51dacb3a76..143d8269c9 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/IE.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/IE.java
@@ -478,7 +478,7 @@ public void create(Composite parent, int style) {
 								long /*int*/ pCancel1 = cancel1.getByRef();
 								OS.MoveMemory(pCancel1, new short[] {OS.VARIANT_FALSE}, 2);
 							}
-							isAboutBlank = false;
+							setAboutBlank(false);
 							break;
 						} else {
 							/*
@@ -536,7 +536,7 @@ public void create(Composite parent, int style) {
 						Variant variant1 = new Variant(auto); /* does not need to be disposed */
 						IDispatch top1 = variant1.getDispatch();
 						if (top1.getAddress() == dispatch1.getAddress()) {
-							isAboutBlank = url1.startsWith(ABOUT_BLANK);
+							setAboutBlank(url1.startsWith(ABOUT_BLANK));
 						}
 					}
 					break;
@@ -701,7 +701,7 @@ public void create(Composite parent, int style) {
 						Variant variant3 = new Variant(auto); /* does not need to be disposed */
 						IDispatch top3 = variant3.getDispatch();
 						if (top3.getAddress() == dispatch3.getAddress()) {
-							isAboutBlank = url3.startsWith(ABOUT_BLANK);
+							setAboutBlank(url3.startsWith(ABOUT_BLANK));
 							lastNavigateURL = url3;
 						}
 					}
@@ -1431,6 +1431,20 @@ void setHTML (String string) {
 	}
 }
 
+private void setAboutBlank(boolean value) {
+	isAboutBlank = value;
+	updateForceTrusted();
+}
+
+private void setUntrustedText(boolean value) {
+	untrustedText = value;
+	updateForceTrusted();
+}
+
+private void updateForceTrusted() {
+	site.isForceTrusted = isAboutBlank && !untrustedText;
+}
+
 @Override
 public boolean setText(final String html, boolean trusted) {
 	/*
@@ -1452,7 +1466,7 @@ public boolean setText(final String html, boolean trusted) {
 	*/
 	boolean blankLoading = this.html != null;
 	this.html = html;
-	untrustedText = !trusted;
+	setUntrustedText(!trusted);
 	if (blankLoading) return true;
 
 	/*
@@ -1567,7 +1581,7 @@ public void stop() {
 	* Ensure that isAboutBlank is set accurately since Stop can be issued at
 	* any stage in the page load cycle.
 	*/
-	isAboutBlank = getUrl().startsWith(ABOUT_BLANK);
+	setAboutBlank(getUrl().startsWith(ABOUT_BLANK));
 
 	uncRedirect = null;
 	int[] rgdispid = auto.getIDsOfNames(new String[] { "Stop" }); //$NON-NLS-1$
diff --git a/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/WebSite.java b/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/WebSite.java
index cdc6d449da..7e46b73010 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/WebSite.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/WebSite.java
@@ -31,6 +31,7 @@ class WebSite extends OleControlSite {
 	COMObject iAuthenticate;
 	COMObject iDispatch;
 	boolean ignoreNextMessage, ignoreAllMessages;
+	boolean isForceTrusted;
 	Boolean canExecuteApplets;
 
 	static final int OLECMDID_SHOWSCRIPTERROR = 40;
@@ -559,12 +560,7 @@ int MapUrlToZone(long /*int*/ pwszUrl, long /*int*/ pdwZone, int dwFlags) {
 	* to follow local links.  The workaround is to return URLZONE_INTRANET
 	* instead of the default value URLZONE_LOCAL_MACHINE.
 	*/
-	IE ie = (IE)((Browser)getParent().getParent()).webBrowser;
-	/*
-	* For some reason IE8 invokes this function after the Browser has
-	* been disposed.  To detect this case check for ie.auto != null.
-	*/
-	if (ie.auto != null && ie.isAboutBlank && !ie.untrustedText) {
+	if (isForceTrusted) {
 		OS.MoveMemory(pdwZone, new int[] {IE.URLZONE_INTRANET}, 4);
 		return COM.S_OK;
 	}